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<!--Created on: 5/5/2026 3:15:43 PM-->
<!--Modified on: 5/5/2026 3:15:43 PM-->
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AmendmentFlag" xlink:to="dei_AmendmentFlag_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AmendmentFlag_lbl" xml:lang="en-US">Amendment Flag</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xml:lang="en-US">Balance Sheets</link:label>
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementTable" xlink:to="us-gaap_StatementTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementTable_lbl" xml:lang="en-US">Statement [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="us-gaap_StatementLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StatementLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementLineItems_lbl" xml:lang="en-US">Statement</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsAbstract" xlink:label="us-gaap_AssetsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsAbstract" xlink:to="us-gaap_AssetsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsAbstract_lbl" xml:lang="en-US">Assets [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AssetsAbstract_lbl" xml:lang="en-US">ASSETS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="us-gaap_AssetsCurrentAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrentAbstract" xlink:to="us-gaap_AssetsCurrentAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US">Assets, Current [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US">Current Assets:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US">Cash and Cash Equivalents, at Carrying Value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherReceivablesNetCurrent" xlink:label="us-gaap_OtherReceivablesNetCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherReceivablesNetCurrent" xlink:to="us-gaap_OtherReceivablesNetCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xml:lang="en-US">Other Receivables, Net, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xml:lang="en-US">Other receivables</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xml:lang="en-US">Prepaid Expense and Other Assets, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrent" xlink:to="us-gaap_AssetsCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US">Assets, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US">Total current assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Assets_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US">Assets</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US">Total Assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US">Liabilities and Equity [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US">LIABILITIES AND STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="us-gaap_LiabilitiesCurrentAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrentAbstract" xlink:to="us-gaap_LiabilitiesCurrentAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US">Liabilities, Current [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US">Current Liabilities:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xml:lang="en-US">Accounts Payable and Accrued Liabilities, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xml:lang="en-US">Total accounts payable and accrued expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xml:lang="en-US">Accounts payable and accrued expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="us-gaap_OtherLiabilitiesCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesCurrent" xlink:to="us-gaap_OtherLiabilitiesCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilitiesCurrent_lbl" xml:lang="en-US">Other Liabilities, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherLiabilitiesCurrent_lbl" xml:lang="en-US">Payables and accrued expenses - related party</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilityCurrentRelatedPartyTypeExtensibleEnumeration" xlink:label="us-gaap_OtherLiabilityCurrentRelatedPartyTypeExtensibleEnumeration" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilityCurrentRelatedPartyTypeExtensibleEnumeration" xlink:to="us-gaap_OtherLiabilityCurrentRelatedPartyTypeExtensibleEnumeration_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilityCurrentRelatedPartyTypeExtensibleEnumeration_lbl" xml:lang="en-US">Other Liability, Current, Related Party [Extensible Enumeration]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrent" xlink:to="us-gaap_LiabilitiesCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US">Liabilities, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US">Total current liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredIncomeNoncurrent" xlink:label="us-gaap_DeferredIncomeNoncurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredIncomeNoncurrent" xlink:to="us-gaap_DeferredIncomeNoncurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredIncomeNoncurrent_lbl" xml:lang="en-US">Deferred Income, Noncurrent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DeferredIncomeNoncurrent_lbl" xml:lang="en-US">Deferred income</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Liabilities" xlink:to="us-gaap_Liabilities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US">Liabilities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US">Total Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="us-gaap_CommitmentsAndContingencies" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xml:lang="en-US">Commitments and Contingencies (Note 8)</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xml:lang="en-US">Stockholders' Equity</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockValue" xlink:label="us-gaap_PreferredStockValue" />
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockValue_lbl" xml:lang="en-US">Common Stock, Value, Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockValue_lbl" xml:lang="en-US">Common stock</link:label>
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesSubscriptions" xlink:to="us-gaap_CommonStockSharesSubscriptions_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesSubscriptions_lbl" xml:lang="en-US">Common Stock, Value, Subscriptions</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesSubscriptions_lbl" xml:lang="en-US">Common stock issuable, zero and 278,385 shares as of March 31, 2026 and December 31, 2025, respectively</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalCommonStock" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xml:lang="en-US">Additional Paid in Capital, Common Stock</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xml:lang="en-US">Additional paid-in capital</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Retained Earnings (Accumulated Deficit)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Accumulated deficit</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Accumulated deficit</link:label>
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquity" xlink:to="us-gaap_StockholdersEquity_lbl" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US">Total Liabilities and Stockholders' Equity</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Preferred Stock, Par or Stated Value Per Share</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Preferred stock par value (in dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="us-gaap_PreferredStockSharesAuthorized" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US">Preferred Stock, Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US">Preferred stock, shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="us-gaap_PreferredStockSharesIssued" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xml:lang="en-US">Preferred Stock, Shares Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xml:lang="en-US">Preferred stock, shares issued</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="us-gaap_PreferredStockSharesOutstanding" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US">Preferred Stock, Shares Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US">Preferred stock, shares outstanding</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Common stock par value (in dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="us-gaap_CommonStockSharesAuthorized" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US">Common stock, shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="us-gaap_CommonStockSharesIssued" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xml:lang="en-US">Common Stock, Shares, Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xml:lang="en-US">Common stock, shares issued</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="us-gaap_CommonStockSharesOutstanding" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xml:lang="en-US">Common Stock, Shares, Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xml:lang="en-US">Common stock, shares outstanding</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesSubscribedButUnissued" xlink:label="us-gaap_CommonStockSharesSubscribedButUnissued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesSubscribedButUnissued" xlink:to="us-gaap_CommonStockSharesSubscribedButUnissued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesSubscribedButUnissued_lbl" xml:lang="en-US">Common Stock, Shares Subscribed but Unissued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesSubscribedButUnissued_lbl" xml:lang="en-US">Common stock, shares issuable</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementAbstract" xlink:label="us-gaap_IncomeStatementAbstract" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xml:lang="en-US">Operating expenses:</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ResearchAndDevelopmentExpenseExcludingAcquiredInProcessCostNet" xlink:label="mbio_ResearchAndDevelopmentExpenseExcludingAcquiredInProcessCostNet" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ResearchAndDevelopmentExpenseExcludingAcquiredInProcessCostNet_lbl" xml:lang="en-US">Research and Development Expense (Excluding Acquired in Process Cost), Net</link:label>
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GeneralAndAdministrativeExpense" xlink:to="us-gaap_GeneralAndAdministrativeExpense_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xml:lang="en-US">General and Administrative Expense</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xml:lang="en-US">General and administrative</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses" xlink:label="us-gaap_OperatingExpenses" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_OperatingExpenses_lbl" xml:lang="en-US">Total operating expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xml:lang="en-US">Loss from operations</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpenseAbstract" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xml:lang="en-US">Nonoperating Income (Expense) [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xml:lang="en-US">Other income</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeOther" xlink:label="us-gaap_InterestIncomeOther" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestIncomeOther_lbl" xml:lang="en-US">Interest Income, Other</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestIncomeOther_lbl" xml:lang="en-US">Interest income, net</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="us-gaap_NonoperatingIncomeExpense" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xml:lang="en-US">Total other income</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US">Net Loss</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xml:lang="en-US">Net loss per Class A common and common shares outstanding, basic</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="us-gaap_EarningsPerShareDiluted" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xml:lang="en-US">Net loss per Class A common and common shares outstanding, diluted</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xml:lang="en-US">Weighted average number of Class A common and common shares outstanding, basic</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US">Weighted average number of Class A common and common shares outstanding, diluted</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xml:lang="en-US">Statements of Stockholders' Equity (Deficit)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredClassAMember" xlink:label="us-gaap_PreferredClassAMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredClassAMember" xlink:to="us-gaap_PreferredClassAMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredClassAMember_lbl" xml:lang="en-US">Preferred Class A [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredClassAMember_lbl" xml:lang="en-US">Class A preferred shares</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_StatementEquityComponentsAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xml:lang="en-US">Equity Components [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_EquityComponentDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquityComponentDomain_lbl" xml:lang="en-US">Equity Component [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockMember" xlink:label="us-gaap_PreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockMember" xlink:to="us-gaap_PreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockMember_lbl" xml:lang="en-US">Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockMember_lbl" xml:lang="en-US">Preferred Stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockMember" xlink:to="us-gaap_CommonStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockMember_lbl" xml:lang="en-US">Common Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CommonStockMember_lbl" xml:lang="en-US">Common Shares</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_CommonStockIssuableMember" xlink:label="mbio_CommonStockIssuableMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_CommonStockIssuableMember" xlink:to="mbio_CommonStockIssuableMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_CommonStockIssuableMember_lbl" xml:lang="en-US">Common Stock Issuable [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="mbio_CommonStockIssuableMember_lbl" xml:lang="en-US">Common Stock Issuable</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="us-gaap_AdditionalPaidInCapitalMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdditionalPaidInCapitalMember" xlink:to="us-gaap_AdditionalPaidInCapitalMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xml:lang="en-US">Additional Paid-in Capital [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xml:lang="en-US">Additional Paid-in Capital</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember" xlink:label="us-gaap_RetainedEarningsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RetainedEarningsMember" xlink:to="us-gaap_RetainedEarningsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US">Retained Earnings [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US">Accumulated Deficit</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesOutstanding" xlink:label="us-gaap_SharesOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharesOutstanding" xlink:to="us-gaap_SharesOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SharesOutstanding_lbl" xml:lang="en-US">Shares, Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_SharesOutstanding_lbl" xml:lang="en-US">Balances (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_SharesOutstanding_lbl" xml:lang="en-US">Balances (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement" xlink:label="mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement" xlink:to="mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement_lbl" xml:lang="en-US">The Value of stock issued in lieu of cash for services contributed to the entity. Value of the stock issued includes, but is not limited to, services contributed by vendors and founders.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement_lbl" xml:lang="en-US">Stock Issued During Period Value Issued For Founders Agreement</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_StockIssuedDuringPeriodValueIssuedForFoundersAgreement_lbl" xml:lang="en-US">Issuance of common shares - Annual Stock Dividend</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:to="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_lbl" xml:lang="en-US">Stock Issued During Period, Shares, Issued for Services</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_lbl" xml:lang="en-US">Shares issued for services (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_lbl" xml:lang="en-US">Issuance of common shares - Annual Stock Dividend (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering" xlink:label="mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering" xlink:to="mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering_lbl" xml:lang="en-US">Value of number of shares issued at equity market offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering_lbl" xml:lang="en-US">Stock Issued During Period Value Equity Fee On At Market Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="mbio_StockIssuedDuringPeriodValueEquityFeeOnAtMarketOffering_lbl" xml:lang="en-US">Issuance of common shares, equity fee on At-the-Market and equity offerings</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering" xlink:to="mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering_lbl" xml:lang="en-US">Common Shares issued equity fee on the market offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering_lbl" xml:lang="en-US">Stock Issued During Period Shares ,Equity Fee On At The Market Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityFeeOnAtMarketOffering_lbl" xml:lang="en-US">Issuance of common shares, equity fee on At-the-Market and equity offerings (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodValueEquityOffering" xlink:label="mbio_StockIssuedDuringPeriodValueEquityOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodValueEquityOffering" xlink:to="mbio_StockIssuedDuringPeriodValueEquityOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodValueEquityOffering_lbl" xml:lang="en-US">Equity impact of the value of new stock issued during the period under equity offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodValueEquityOffering_lbl" xml:lang="en-US">Stock Issued During Period, Value, Equity Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_StockIssuedDuringPeriodValueEquityOffering_lbl" xml:lang="en-US">Issuance of common shares, net of offering costs - Equity Offerings</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodSharesEquityOffering" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodSharesEquityOffering" xlink:to="mbio_StockIssuedDuringPeriodSharesEquityOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityOffering_lbl" xml:lang="en-US">Number of new stock issued during the period under equity offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityOffering_lbl" xml:lang="en-US">Stock Issued During Period, Shares, Equity Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_StockIssuedDuringPeriodSharesEquityOffering_lbl" xml:lang="en-US">Issuance of common shares, net of offering costs - Equity Offerings (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodValueAtMarketingOffering" xlink:label="mbio_StockIssuedDuringPeriodValueAtMarketingOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodValueAtMarketingOffering" xlink:to="mbio_StockIssuedDuringPeriodValueAtMarketingOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodValueAtMarketingOffering_lbl" xml:lang="en-US">Value of stock issued at the market offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodValueAtMarketingOffering_lbl" xml:lang="en-US">Stock Issued During Period Value, At The Marketing Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="mbio_StockIssuedDuringPeriodValueAtMarketingOffering_lbl" xml:lang="en-US">Issuance of common shares, net of offering costs - At-the-Market Offering</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_StockIssuedDuringPeriodSharesAtMarketOffering" xlink:label="mbio_StockIssuedDuringPeriodSharesAtMarketOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_StockIssuedDuringPeriodSharesAtMarketOffering" xlink:to="mbio_StockIssuedDuringPeriodSharesAtMarketOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_StockIssuedDuringPeriodSharesAtMarketOffering_lbl" xml:lang="en-US">Number of shares issued at the market offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_StockIssuedDuringPeriodSharesAtMarketOffering_lbl" xml:lang="en-US">Stock Issued During Period Shares , At The Market Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="mbio_StockIssuedDuringPeriodSharesAtMarketOffering_lbl" xml:lang="en-US">Issuance of common shares, net of offering costs - At-the-Market Offering (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:label="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:to="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_lbl" xml:lang="en-US">Stock Issued During Period, Value, Employee Stock Purchase Plan</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_lbl" xml:lang="en-US">Issuance of common shares under ESPP</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:to="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_lbl" xml:lang="en-US">Stock Issued During Period, Shares, Employee Stock Purchase Plans</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_lbl" xml:lang="en-US">Issuance of common shares under ESPP (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:to="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xml:lang="en-US">Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xml:lang="en-US">Stock-based compensation expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:to="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xml:lang="en-US">Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xml:lang="en-US">Stock-based compensation expenses (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AbeyanceSharesReleased" xlink:label="mbio_AbeyanceSharesReleased" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AbeyanceSharesReleased" xlink:to="mbio_AbeyanceSharesReleased_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AbeyanceSharesReleased_lbl" xml:lang="en-US">Number of abeyance shares released during the period.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AbeyanceSharesReleased_lbl" xml:lang="en-US">Abeyance Shares Released</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AbeyanceSharesReleased_lbl" xml:lang="en-US">Abeyance Shares released (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants" xlink:label="mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants" xlink:to="mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants_lbl" xml:lang="en-US">The value of shares issued on exercise of warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants_lbl" xml:lang="en-US">Share Issued During Period, Value, On Exercise Of Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ShareIssuedDuringPeriodValueOnExerciseOfWarrants_lbl" xml:lang="en-US">Exercise of warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants" xlink:label="mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants" xlink:to="mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants_lbl" xml:lang="en-US">The number of shares issued on exercise of warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants_lbl" xml:lang="en-US">Share Issued During Period, Shares, On Exercise Of Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ShareIssuedDuringPeriodSharesOnExerciseOfWarrants_lbl" xml:lang="en-US">Exercise of warrants (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits" xlink:label="mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits" xlink:to="mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits_lbl" xml:lang="en-US">The amount of additions (reductions) to additional paid-in capital during the period attributable to reverse stock splits.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits_lbl" xml:lang="en-US">Additions (Reductions) To Additional Paid In Capital, Reverse Stock Splits</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AdditionsReductionsToAdditionalPaidInCapitalReverseStockSplits_lbl" xml:lang="en-US">Reverse Split (1-for-50) adjustment</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_NumberOfSharesReverseStockSplit" xlink:label="mbio_NumberOfSharesReverseStockSplit" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_NumberOfSharesReverseStockSplit" xlink:to="mbio_NumberOfSharesReverseStockSplit_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_NumberOfSharesReverseStockSplit_lbl" xml:lang="en-US">Number of shares attributable to reverse stock split.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_NumberOfSharesReverseStockSplit_lbl" xml:lang="en-US">Number of Shares, Reverse Stock Split</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="mbio_NumberOfSharesReverseStockSplit_lbl" xml:lang="en-US">Reverse Split (1-for-50) adjustment (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:to="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xml:lang="en-US">Stockholders' Equity Note, Stock Split, Conversion Ratio</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xml:lang="en-US">Reverse split ratio</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="us-gaap_StatementOfCashFlowsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_StatementOfCashFlowsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xml:lang="en-US">Statements of Cash Flows</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Cash Flows from Operating Activities:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Adjustments to reconcile net loss to net cash used in operating activities:</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering" xlink:label="mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering" xlink:to="mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering_lbl" xml:lang="en-US">Amount of equity fee on equity offering for issuance of common shares.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering_lbl" xml:lang="en-US">Issuance of Common Shares Equity Fee on Equity Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_IssuanceOfCommonSharesEquityFeeOnEquityOffering_lbl" xml:lang="en-US">Issuance of common shares - equity fee on equity offerings to Fortress Biotech</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensation" xlink:to="us-gaap_ShareBasedCompensation_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Share-Based Payment Arrangement, Noncash Expense</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Total stock-based compensation expense</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Stock-based compensation expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Depreciation" xlink:label="us-gaap_Depreciation" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Depreciation" xlink:to="us-gaap_Depreciation_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Depreciation_lbl" xml:lang="en-US">Depreciation</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_Depreciation_lbl" xml:lang="en-US">Depreciation expense</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense" xlink:to="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_lbl" xml:lang="en-US">Operating Lease, Right-of-Use Asset, Periodic Reduction</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_lbl" xml:lang="en-US">Amortization of operating lease right-of-use assets</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_NoncashSettlementOfPayables" xlink:label="mbio_NoncashSettlementOfPayables" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_NoncashSettlementOfPayables" xlink:to="mbio_NoncashSettlementOfPayables_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_NoncashSettlementOfPayables_lbl" xml:lang="en-US">Amount of payables settled that result in no cashflow.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_NoncashSettlementOfPayables_lbl" xml:lang="en-US">Noncash Settlement Of Payables</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="mbio_NoncashSettlementOfPayables_lbl" xml:lang="en-US">Settlement of payables</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_GainOnLeaseModification" xlink:label="mbio_GainOnLeaseModification" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_GainOnLeaseModification" xlink:to="mbio_GainOnLeaseModification_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_GainOnLeaseModification_lbl" xml:lang="en-US">Amount of gain (loss) on modification of lease before expiration of lease term.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_GainOnLeaseModification_lbl" xml:lang="en-US">Gain on lease modification</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="mbio_GainOnLeaseModification_lbl" xml:lang="en-US">Gain on lease termination</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US">Changes in operating assets and liabilities:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xml:lang="en-US">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xml:lang="en-US">Prepaid expenses and other assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherReceivables" xlink:label="us-gaap_IncreaseDecreaseInOtherReceivables" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherReceivables" xlink:to="us-gaap_IncreaseDecreaseInOtherReceivables_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOtherReceivables_lbl" xml:lang="en-US">Increase (Decrease) in Other Receivables</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInOtherReceivables_lbl" xml:lang="en-US">Other receivables</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties" xlink:label="mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties" xlink:to="mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties_lbl" xml:lang="en-US">The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid excluding those attributable to related parties.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties_lbl" xml:lang="en-US">Increase (Decrease) In Accounts Payable And Accrued Expenses Excluding Amounts Due To Related Parties</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_IncreaseDecreaseInAccountsPayableAndAccruedExpensesExcludingAmountsDueToRelatedParties_lbl" xml:lang="en-US">Accounts payable and accrued expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInDueToRelatedParties" xlink:label="us-gaap_IncreaseDecreaseInDueToRelatedParties" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInDueToRelatedParties" xlink:to="us-gaap_IncreaseDecreaseInDueToRelatedParties_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInDueToRelatedParties_lbl" xml:lang="en-US">Increase (Decrease) in Due to Related Parties</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncreaseDecreaseInDueToRelatedParties_lbl" xml:lang="en-US">Payable and accrued expenses - related party</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_IncreaseDecreaseInLeaseLiabilities" xlink:label="mbio_IncreaseDecreaseInLeaseLiabilities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_IncreaseDecreaseInLeaseLiabilities" xlink:to="mbio_IncreaseDecreaseInLeaseLiabilities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_IncreaseDecreaseInLeaseLiabilities_lbl" xml:lang="en-US">Amount of Increase Decrease In Lease Liabilities.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_IncreaseDecreaseInLeaseLiabilities_lbl" xml:lang="en-US">Increase Decrease In Lease Liabilities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="mbio_IncreaseDecreaseInLeaseLiabilities_lbl" xml:lang="en-US">Lease liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xml:lang="en-US">Net cash used in operating activities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xml:lang="en-US">Cash Flows from Investing Activities:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xml:lang="en-US">Proceeds from Sale of Property, Plant, and Equipment</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xml:lang="en-US">Proceeds from the sale of property and equipment</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xml:lang="en-US">Net cash from investing activities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xml:lang="en-US">Cash Flows from Financing Activities:</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering" xlink:label="mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering" xlink:to="mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering_lbl" xml:lang="en-US">Amount of cash inflow from issuance of common stock at an equity offering, net of offering expenses.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering_lbl" xml:lang="en-US">Proceeds From Issuance Of Common Stock, Net Of Issuance Costs At Equity Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCostsAtEquityOffering_lbl" xml:lang="en-US">Proceeds from issuance of common shares, net of offering costs - equity offering</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering" xlink:label="mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering" xlink:to="mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering_lbl" xml:lang="en-US">Proceeds from issuance of common shares - At-the-Market Offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering_lbl" xml:lang="en-US">Proceeds From Issuance of Common Shares - At-the-Market Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ProceedsFromIssuanceOfCommonSharesAtMarketOffering_lbl" xml:lang="en-US">Proceeds from issuance of common shares, net of offering costs - At-the-Market offering</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xml:lang="en-US">Net cash provided by financing activities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xml:lang="en-US">Net change in cash and cash equivalents</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xml:lang="en-US">Cash and cash equivalents, end of the period</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xml:lang="en-US">Cash and cash equivalents, beginning of the period</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:to="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xml:lang="en-US">Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xml:lang="en-US">Supplemental disclosure of noncash activities:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssued1" xlink:label="us-gaap_StockIssued1" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssued1" xlink:to="us-gaap_StockIssued1_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssued1_lbl" xml:lang="en-US">Stock Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssued1_lbl" xml:lang="en-US">Issuance of common shares - Founders Agreement and equity fee to Fortress</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering" xlink:label="mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering" xlink:to="mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering_lbl" xml:lang="en-US">Unpaid offering costs for the issuance of equity offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering_lbl" xml:lang="en-US">Unpaid Offering Costs For Issuance of Equity Offering</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_UnpaidOfferingCostsForIssuanceOfEquityOffering_lbl" xml:lang="en-US">Unpaid offering costs - equity offering</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xml:lang="en-US">Organization, Description of Business and Liquidity and Capital Resources</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" xml:lang="en-US">Organization, Description of Business and Liquidity and Capital Resources</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_AccountingPoliciesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xml:lang="en-US">Significant Accounting Policies</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SignificantAccountingPoliciesTextBlock" xlink:to="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xml:lang="en-US">Significant Accounting Policies [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xml:lang="en-US">Significant Accounting Policies</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="us-gaap_RelatedPartyTransactionsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RelatedPartyTransactionsAbstract" xlink:to="us-gaap_RelatedPartyTransactionsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_lbl" xml:lang="en-US">Related Party Agreements</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xml:lang="en-US">Related Party Transaction [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="us-gaap_RelatedPartyTransactionLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RelatedPartyTransactionLineItems" xlink:to="us-gaap_RelatedPartyTransactionLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xml:lang="en-US">Related Party Agreements</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:to="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xml:lang="en-US">Related Party Transactions Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xml:lang="en-US">Related Party Agreements</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="us-gaap_PayablesAndAccrualsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PayablesAndAccrualsAbstract" xlink:to="us-gaap_PayablesAndAccrualsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xml:lang="en-US">Accounts Payable and Accrued Expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock" xlink:to="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xml:lang="en-US">Accounts Payable and Accrued Liabilities Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xml:lang="en-US">Accounts Payable and Accrued Expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityNoteAbstract" xlink:label="us-gaap_StockholdersEquityNoteAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityNoteAbstract" xlink:to="us-gaap_StockholdersEquityNoteAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityNoteAbstract_lbl" xml:lang="en-US">Stockholders' Equity</link:label>
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:to="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xml:lang="en-US">Net Loss per Share</link:label>
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationAllowanceTable" xlink:label="us-gaap_ValuationAllowanceTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ValuationAllowanceTable" xlink:to="us-gaap_ValuationAllowanceTable_lbl" />
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationAllowanceLineItems" xlink:label="us-gaap_ValuationAllowanceLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ValuationAllowanceLineItems" xlink:to="us-gaap_ValuationAllowanceLineItems_lbl" />
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xml:lang="en-US">Commitments and Contingencies Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xml:lang="en-US">Commitments and Contingencies</link:label>
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="us-gaap_SubsequentEventsTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventsTextBlock" xlink:to="us-gaap_SubsequentEventsTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xml:lang="en-US">Subsequent Events</link:label>
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    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:to="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xml:lang="en-US">Basis of Presentation</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xml:lang="en-US">Segment Reporting</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_SignificantAccountingPoliciesPolicyTextBlock" xlink:label="mbio_SignificantAccountingPoliciesPolicyTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xml:lang="en-US">Recently Issued Accounting Standards</link:label>
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xml:lang="en-US">Schedule of Potentially Dilutive Securities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:to="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xml:lang="en-US">Sale of Stock, Consideration Received on Transaction</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xml:lang="en-US">Net proceeds of offering</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="us-gaap_ScheduleOfStockByClassTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="us-gaap_ScheduleOfStockByClassTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfStockByClassTable_lbl" xml:lang="en-US">Stockholders' Equity.</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockLineItems" xlink:label="us-gaap_ClassOfStockLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ClassOfStockLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfStockLineItems_lbl" xml:lang="en-US">Class of Stock [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfStockLineItems_lbl" xml:lang="en-US">Significant Accounting Policies</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="us-gaap_NumberOfOperatingSegments" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NumberOfOperatingSegments" xlink:to="us-gaap_NumberOfOperatingSegments_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xml:lang="en-US">Number of Operating Segments</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xml:lang="en-US">Number of operating segments</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xml:lang="en-US">Related and Nonrelated Parties [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="us-gaap_RelatedPartyDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyDomain_lbl" xml:lang="en-US">Related and Nonrelated Parties [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember" xlink:label="us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember" xlink:to="us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember_lbl" xml:lang="en-US">Majority-Owned Subsidiary, Nonconsolidated [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember_lbl" xml:lang="en-US">Parent Company</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="us-gaap_TypeOfArrangementAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_TypeOfArrangementAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xml:lang="en-US">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xml:lang="en-US">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ManagementServicesAgreementMember" xlink:label="mbio_ManagementServicesAgreementMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ManagementServicesAgreementMember" xlink:to="mbio_ManagementServicesAgreementMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ManagementServicesAgreementMember_lbl" xml:lang="en-US">Management Services Agreement [Member].</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ManagementServicesAgreementMember_lbl" xml:lang="en-US">Management Services Agreement [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ManagementServicesAgreementMember_lbl" xml:lang="en-US">Management Services Agreement (MSA)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_SecondAmendedAndRestatedFoundersAgreementMember" xlink:label="mbio_SecondAmendedAndRestatedFoundersAgreementMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_SecondAmendedAndRestatedFoundersAgreementMember" xlink:to="mbio_SecondAmendedAndRestatedFoundersAgreementMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_SecondAmendedAndRestatedFoundersAgreementMember_lbl" xml:lang="en-US">Second Amended and Restated Founders Agreement [Member].</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_SecondAmendedAndRestatedFoundersAgreementMember_lbl" xml:lang="en-US">Second Amended and Restated Founders Agreement [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_SecondAmendedAndRestatedFoundersAgreementMember_lbl" xml:lang="en-US">Founders Agreement</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CounterpartyNameAxis" xlink:label="srt_CounterpartyNameAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_CounterpartyNameAxis" xlink:to="srt_CounterpartyNameAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_CounterpartyNameAxis_lbl" xml:lang="en-US">Counterparty Name [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xml:lang="en-US">Counterparty Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_FortressBiotechIncMember" xlink:label="mbio_FortressBiotechIncMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_FortressBiotechIncMember" xlink:to="mbio_FortressBiotechIncMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_FortressBiotechIncMember_lbl" xml:lang="en-US">Fortress Biotech, Inc [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_FortressBiotechIncMember_lbl" xml:lang="en-US">Fortress Biotech, Inc</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_PercentageOfAnnualFeesExpensesRelatedToManagementServicesAgreementRecordedInResearchAndDevelopmentExpenses" xlink:label="mbio_PercentageOfAnnualFeesExpensesRelatedToManagementServicesAgreementRecordedInResearchAndDevelopmentExpenses" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_PercentageOfAnnualFeesExpensesRelatedToManagementServicesAgreementRecordedInResearchAndDevelopmentExpenses_lbl" xml:lang="en-US">Percentage of annual fees expense related to Management Services Agreement recorded in research and development expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_PercentageOfAnnualFeesExpensesRelatedToManagementServicesAgreementRecordedInResearchAndDevelopmentExpenses_lbl" xml:lang="en-US">Percentage of Annual Fees Expenses Related to Management Services Agreement recorded in research and development expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_PercentageOfAnnualFeesExpensesRelatedToManagementServicesAgreementRecordedInResearchAndDevelopmentExpenses_lbl" xml:lang="en-US">Percentage of annual fees expense related to Management Services Agreement recorded in research and development expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_PercentageOfAnnualFeesExpenseRelatedToManagementServicesAgreementRecordedInGeneralAndAdministrativeExpenses" xlink:label="mbio_PercentageOfAnnualFeesExpenseRelatedToManagementServicesAgreementRecordedInGeneralAndAdministrativeExpenses" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_PercentageOfAnnualFeesExpenseRelatedToManagementServicesAgreementRecordedInGeneralAndAdministrativeExpenses_lbl" xml:lang="en-US">Percentage of annual fees expense related to Management Services Agreement recorded in general and administrative expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_PercentageOfAnnualFeesExpenseRelatedToManagementServicesAgreementRecordedInGeneralAndAdministrativeExpenses_lbl" xml:lang="en-US">Percentage of annual fees expense related to Management Services Agreement recorded in general and administrative expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_PercentageOfAnnualFeesExpenseRelatedToManagementServicesAgreementRecordedInGeneralAndAdministrativeExpenses_lbl" xml:lang="en-US">Percentage of annual fees expense related to Management Services Agreement recorded in general and administrative expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingCostsAndExpenses" xlink:label="us-gaap_OperatingCostsAndExpenses" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingCostsAndExpenses_lbl" xml:lang="en-US">Operating Costs and Expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingCostsAndExpenses_lbl" xml:lang="en-US">Expenses from related party transaction</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_DilutedOutstandingEquityPercentage" xlink:label="mbio_DilutedOutstandingEquityPercentage" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_DilutedOutstandingEquityPercentage_lbl" xml:lang="en-US">Represents the percentage of diluted outstanding equity paid as equity fee or used to calculate stock issuance to maintain parity.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_DilutedOutstandingEquityPercentage_lbl" xml:lang="en-US">Diluted Outstanding Equity, Percentage</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_DilutedOutstandingEquityPercentage_lbl" xml:lang="en-US">Percentage of fully diluted equity</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOff" xlink:label="us-gaap_ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOff" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOff_lbl" xml:lang="en-US">Research and Development Asset Acquired in Transaction Other than Business Combination or Joint Venture Formation, Writeoff</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOff_lbl" xml:lang="en-US">Research and development for expense acquired</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AccountsPayableAndAccruedExpensesTable" xlink:label="mbio_AccountsPayableAndAccruedExpensesTable" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AccountsPayableAndAccruedExpensesTable_lbl" xml:lang="en-US">Accounts Payable and Accrued Expenses [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AccountsPayableAndAccruedExpensesLineItems" xlink:label="mbio_AccountsPayableAndAccruedExpensesLineItems" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AccountsPayableAndAccruedExpensesLineItems_lbl" xml:lang="en-US">Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AccountsPayableAndAccruedExpensesLineItems_lbl" xml:lang="en-US">Accounts Payable and Accrued Expenses [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AccountsPayableAndAccruedExpensesLineItems_lbl" xml:lang="en-US">Accounts Payable and Accrued Expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsPayableCurrent" xlink:to="us-gaap_AccountsPayableCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xml:lang="en-US">Accounts Payable, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xml:lang="en-US">Accounts payable</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ResearchAndDevelopmentCurrent" xlink:label="mbio_ResearchAndDevelopmentCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ResearchAndDevelopmentCurrent" xlink:to="mbio_ResearchAndDevelopmentCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ResearchAndDevelopmentCurrent_lbl" xml:lang="en-US">Carrying value as of the balance sheet date of obligations incurred and payable for research and development.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ResearchAndDevelopmentCurrent_lbl" xml:lang="en-US">Research and Development Current</link:label>
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    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AccruedCompensationCurrent" xlink:label="mbio_AccruedCompensationCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AccruedCompensationCurrent" xlink:to="mbio_AccruedCompensationCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AccruedCompensationCurrent_lbl" xml:lang="en-US">Carrying value as of the balance sheet date of obligations incurred through that date and payable for accrued compensation.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AccruedCompensationCurrent_lbl" xml:lang="en-US">Accrued Compensation Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AccruedCompensationCurrent_lbl" xml:lang="en-US">Accrued compensation</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAccountsPayableAndAccruedLiabilities" xlink:label="us-gaap_OtherAccountsPayableAndAccruedLiabilities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherAccountsPayableAndAccruedLiabilities" xlink:to="us-gaap_OtherAccountsPayableAndAccruedLiabilities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherAccountsPayableAndAccruedLiabilities_lbl" xml:lang="en-US">Other Accounts Payable and Accrued Liabilities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherAccountsPayableAndAccruedLiabilities_lbl" xml:lang="en-US">Other</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetAcquisitionAxis" xlink:label="us-gaap_AssetAcquisitionAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetAcquisitionAxis" xlink:to="us-gaap_AssetAcquisitionAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetAcquisitionAxis_lbl" xml:lang="en-US">Asset Acquisition [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetAcquisitionDomain" xlink:label="us-gaap_AssetAcquisitionDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetAcquisitionDomain" xlink:to="us-gaap_AssetAcquisitionDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetAcquisitionDomain_lbl" xml:lang="en-US">Asset Acquisition [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember" xlink:label="mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember" xlink:to="mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember_lbl" xml:lang="en-US">Represents information pertaining to Asset Purchase Agreement with uBriGene (Boston) Biosciences, Inc.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember_lbl" xml:lang="en-US">Asset Purchase Agreement with Ubrigene Biosciences [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetPurchaseAgreementWithUbrigeneBiosciencesMember_lbl" xml:lang="en-US">Repurchase of Assets</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment" xlink:label="mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment" xlink:to="mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment_lbl" xml:lang="en-US">Amount of subsequent consideration recognized as part of consideration transferred in asset acquisition.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment_lbl" xml:lang="en-US">Asset Acquisition, Consideration Transferred, Subsequent Payment</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetAcquisitionConsiderationTransferredSubsequentPayment_lbl" xml:lang="en-US">Subsequent payment</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration" xlink:label="mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration" xlink:to="mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration_lbl" xml:lang="en-US">Amount of accrued interest  on deferred purchase consideration arising from an asset acquisition.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration_lbl" xml:lang="en-US">Asset Acquisition, Accrued Interest On Deferred Purchase Consideration</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetAcquisitionAccruedInterestOnDeferredPurchaseConsideration_lbl" xml:lang="en-US">Accrued interest</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment" xlink:label="mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment" xlink:to="mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment_lbl" xml:lang="en-US">Amount of upfront consideration recognized as part of consideration transferred in asset acquisition.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment_lbl" xml:lang="en-US">Asset Acquisition, Consideration Transferred, Upfront Payment</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetAcquisitionConsiderationTransferredUpfrontPayment_lbl" xml:lang="en-US">Upfront payment</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate" xlink:to="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate_lbl" xml:lang="en-US">Represents the due period for deferred payment from Effective Date in an asset acquisition.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate_lbl" xml:lang="en-US">Asset Acquisition, Consideration Transferred, Deferred Payment, Due Period from Closing Date</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentDuePeriodFromClosingDate_lbl" xml:lang="en-US">Subsequent amount, due period from closing date</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm" xlink:to="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm_lbl" xml:lang="en-US">Represents the extension term for delay in payment of deferred payment.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm_lbl" xml:lang="en-US">Asset Acquisition, Consideration Transferred, Deferred Payment, Extension Term</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentExtensionTerm_lbl" xml:lang="en-US">Extension term for deferred payment</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation" xlink:label="mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation" xlink:to="mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation_lbl" xml:lang="en-US">Amount of net assets below this threshold, then the Company may, upon written notice to uBriGene, elect to delay its payment obligation of the Deferred Amount by an additional six (6) months, with no limit on the number of such extensions available to the Company.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation_lbl" xml:lang="en-US">Net Assets Threshold to Delay Consideration Payment Obligation</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_NetAssetsThresholdToDelayConsiderationPaymentObligation_lbl" xml:lang="en-US">Amount of net assets below this threshold, the Company may elect to delay payment obligation by additional six months</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability" xlink:to="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability_lbl" xml:lang="en-US">Represents percentage of interest accrual on outstanding liability of deferred payment in asset acquisition transaction.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability_lbl" xml:lang="en-US">Asset Acquisition, Consideration Transferred, Deferred Payment, Interest Rate on Outstanding Liability</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AssetAcquisitionConsiderationTransferredDeferredPaymentInterestRateOnOutstandingLiability_lbl" xml:lang="en-US">Interest rate on outstanding Deferred Amount</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="us-gaap_SubsidiarySaleOfStockAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsidiarySaleOfStockAxis" xlink:to="us-gaap_SubsidiarySaleOfStockAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xml:lang="en-US">Sale of Stock [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xml:lang="en-US">Sale of Stock [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_RegistrationStatementsMember" xlink:label="mbio_RegistrationStatementsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_RegistrationStatementsMember" xlink:to="mbio_RegistrationStatementsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_RegistrationStatementsMember_lbl" xml:lang="en-US">Registration Statements [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_RegistrationStatementsMember_lbl" xml:lang="en-US">Registration Statements [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_RegistrationStatementsMember_lbl" xml:lang="en-US">Registration Statements</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_RegistrationStatements2024S3Member" xlink:label="mbio_RegistrationStatements2024S3Member" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_RegistrationStatements2024S3Member" xlink:to="mbio_RegistrationStatements2024S3Member_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_RegistrationStatements2024S3Member_lbl" xml:lang="en-US">Registration Statements, 2024 S-3 [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_RegistrationStatements2024S3Member_lbl" xml:lang="en-US">Registration Statements, 2024 S-3 [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_RegistrationStatements2024S3Member_lbl" xml:lang="en-US">2024 S-3</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement" xlink:label="mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement" xlink:to="mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement_lbl" xml:lang="en-US">Sale of Stock aggregate offering price permitted by agreement.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement_lbl" xml:lang="en-US">Sale of Stock aggregate offering price permitted by agreement</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_SaleOfStockAggregateOfferingPricePermittedByAgreement_lbl" xml:lang="en-US">Sale of Stock aggregate offering price</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_CommonStockSharesAvailableForFutureIssuanceValue" xlink:label="mbio_CommonStockSharesAvailableForFutureIssuanceValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_CommonStockSharesAvailableForFutureIssuanceValue" xlink:to="mbio_CommonStockSharesAvailableForFutureIssuanceValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_CommonStockSharesAvailableForFutureIssuanceValue_lbl" xml:lang="en-US">Common Stock Shares Available For Future Issuance Value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_CommonStockSharesAvailableForFutureIssuanceValue_lbl" xml:lang="en-US">Common Stock Shares Available For Future Issuance Value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_CommonStockSharesAvailableForFutureIssuanceValue_lbl" xml:lang="en-US">Shares available for future issuance</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_February2025PublicOfferingMember" xlink:label="mbio_February2025PublicOfferingMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_February2025PublicOfferingMember" xlink:to="mbio_February2025PublicOfferingMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_February2025PublicOfferingMember_lbl" xml:lang="en-US">Represents information pertaining to February 2025 Public offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_February2025PublicOfferingMember_lbl" xml:lang="en-US">February 2025 Public Offering [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_February2025PublicOfferingMember_lbl" xml:lang="en-US">February 2025 Equity Offering</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xml:lang="en-US">Class of Warrant or Right [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xml:lang="en-US">Class of Warrant or Right [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_PrefundedWarrantsMember" xlink:label="mbio_PrefundedWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_PrefundedWarrantsMember" xlink:to="mbio_PrefundedWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_PrefundedWarrantsMember_lbl" xml:lang="en-US">Represents the information pertaining to prefunded warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_PrefundedWarrantsMember_lbl" xml:lang="en-US">Prefunded Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_PrefundedWarrantsMember_lbl" xml:lang="en-US">Pre-Funded Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_SeriesC1WarrantMember" xlink:label="mbio_SeriesC1WarrantMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_SeriesC1WarrantMember" xlink:to="mbio_SeriesC1WarrantMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_SeriesC1WarrantMember_lbl" xml:lang="en-US">Represents information pertaining to Series C1 warrant.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_SeriesC1WarrantMember_lbl" xml:lang="en-US">Series C1 Warrant [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_SeriesC1WarrantMember_lbl" xml:lang="en-US">Series C-1 Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_SeriesC2WarrantMember" xlink:label="mbio_SeriesC2WarrantMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_SeriesC2WarrantMember" xlink:to="mbio_SeriesC2WarrantMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_SeriesC2WarrantMember_lbl" xml:lang="en-US">Represents information pertaining to Series C2 warrant.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_SeriesC2WarrantMember_lbl" xml:lang="en-US">Series C2 Warrant [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_SeriesC2WarrantMember_lbl" xml:lang="en-US">Series C-2 Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_SeriesA3WarrantMember" xlink:label="mbio_SeriesA3WarrantMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_SeriesA3WarrantMember" xlink:to="mbio_SeriesA3WarrantMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_SeriesA3WarrantMember_lbl" xml:lang="en-US">Represents the information pertaining to series A-3 warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_SeriesA3WarrantMember_lbl" xml:lang="en-US">Series A3 Warrant [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_SeriesA3WarrantMember_lbl" xml:lang="en-US">Series A-3 warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_PlacementAgentsWarrantsMember" xlink:label="mbio_PlacementAgentsWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_PlacementAgentsWarrantsMember" xlink:to="mbio_PlacementAgentsWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_PlacementAgentsWarrantsMember_lbl" xml:lang="en-US">Represents the information pertaining to placement agents warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_PlacementAgentsWarrantsMember_lbl" xml:lang="en-US">Placement Agents Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_PlacementAgentsWarrantsMember_lbl" xml:lang="en-US">Placement Agents Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_RangeAxis" xlink:to="srt_RangeAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_RangeAxis_lbl" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember" xlink:label="srt_RangeMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_RangeMember" xlink:to="srt_RangeMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_RangeMember_lbl" xml:lang="en-US">Statistical Measurement [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember" xlink:label="srt_MaximumMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_MaximumMember" xlink:to="srt_MaximumMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_MaximumMember_lbl" xml:lang="en-US">Maximum [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="srt_MaximumMember_lbl" xml:lang="en-US">Maximum</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US">Stock Issued During Period, Shares, New Issues</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US">Issuance of common shares (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US">Warrants issued</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ClassOfWarrantConverted" xlink:label="mbio_ClassOfWarrantConverted" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ClassOfWarrantConverted" xlink:to="mbio_ClassOfWarrantConverted_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ClassOfWarrantConverted_lbl" xml:lang="en-US">Number of  warrant or right may be converted.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ClassOfWarrantConverted_lbl" xml:lang="en-US">Class of Warrant Converted</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ClassOfWarrantConverted_lbl" xml:lang="en-US">Number of warrant to converted</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Each Warrant or Right</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" xml:lang="en-US">Number of common stock, each warrant get converted</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="us-gaap_SaleOfStockPricePerShare" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockPricePerShare" xlink:to="us-gaap_SaleOfStockPricePerShare_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xml:lang="en-US">Sale of Stock, Price Per Share</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xml:lang="en-US">Price per share</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:to="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US">Class of Warrant or Right, Exercise Price of Warrants or Rights</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US">Warrant exercise price (in dollars per share)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US">Exercise price of warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantsAndRightsOutstandingTerm" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WarrantsAndRightsOutstandingTerm" xlink:to="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xml:lang="en-US">Warrants and Rights Outstanding, Term</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xml:lang="en-US">Warrants expiration term</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightOutstanding" xlink:to="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US">Class of Warrant or Right, Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US">Warrants Outstanding, ending</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US">Warrants Outstanding, beginning</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US">Number of warrants outstanding</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_CashFeeAsPercentageOfAggregateGrossProceeds" xlink:label="mbio_CashFeeAsPercentageOfAggregateGrossProceeds" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_CashFeeAsPercentageOfAggregateGrossProceeds" xlink:to="mbio_CashFeeAsPercentageOfAggregateGrossProceeds_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_CashFeeAsPercentageOfAggregateGrossProceeds_lbl" xml:lang="en-US">The cash fee payable as a percentage of gross proceeds from the exercise of existing warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_CashFeeAsPercentageOfAggregateGrossProceeds_lbl" xml:lang="en-US">Cash Fee As percentage Of Aggregate Gross proceeds</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_CashFeeAsPercentageOfAggregateGrossProceeds_lbl" xml:lang="en-US">Cash fee as percentage of aggregate gross proceeds</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ManagementFeeAsPercentageOfGrossProceeds" xlink:label="mbio_ManagementFeeAsPercentageOfGrossProceeds" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ManagementFeeAsPercentageOfGrossProceeds" xlink:to="mbio_ManagementFeeAsPercentageOfGrossProceeds_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ManagementFeeAsPercentageOfGrossProceeds_lbl" xml:lang="en-US">The management fee payable as a percentage of gross proceeds raised.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ManagementFeeAsPercentageOfGrossProceeds_lbl" xml:lang="en-US">Management Fee As Percentage Of Gross Proceeds</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ManagementFeeAsPercentageOfGrossProceeds_lbl" xml:lang="en-US">Management fee as percentage of gross proceeds</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_FeesAndOtherRelatedExpenses" xlink:label="mbio_FeesAndOtherRelatedExpenses" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_FeesAndOtherRelatedExpenses" xlink:to="mbio_FeesAndOtherRelatedExpenses_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_FeesAndOtherRelatedExpenses_lbl" xml:lang="en-US">The fees associated with the services provided by the Placement Agent's counsel and other out of pocket expenses.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_FeesAndOtherRelatedExpenses_lbl" xml:lang="en-US">Fees And Other Related Expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_FeesAndOtherRelatedExpenses_lbl" xml:lang="en-US">Fees and expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_NonAccountableExpenseAllowance" xlink:label="mbio_NonAccountableExpenseAllowance" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_NonAccountableExpenseAllowance" xlink:to="mbio_NonAccountableExpenseAllowance_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_NonAccountableExpenseAllowance_lbl" xml:lang="en-US">Amount of non-accountable expense allowance paid to placement agent.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_NonAccountableExpenseAllowance_lbl" xml:lang="en-US">Non Accountable Expense Allowance</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_NonAccountableExpenseAllowance_lbl" xml:lang="en-US">Non accountable expense allowance</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_RoadShowExpenses" xlink:label="mbio_RoadShowExpenses" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_RoadShowExpenses" xlink:to="mbio_RoadShowExpenses_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_RoadShowExpenses_lbl" xml:lang="en-US">Amount of organizing and conducting road shows by placement agent.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_RoadShowExpenses_lbl" xml:lang="en-US">Road Show Expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_RoadShowExpenses_lbl" xml:lang="en-US">Road show expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ClearingExpenses" xlink:label="mbio_ClearingExpenses" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ClearingExpenses" xlink:to="mbio_ClearingExpenses_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ClearingExpenses_lbl" xml:lang="en-US">Expenses associated with the clearing and settlement of securities transactions.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ClearingExpenses_lbl" xml:lang="en-US">Clearing Expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ClearingExpenses_lbl" xml:lang="en-US">Clearing expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_PrefundedWarrantAndShareSoldInOfferingPercentage" xlink:label="mbio_PrefundedWarrantAndShareSoldInOfferingPercentage" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_PrefundedWarrantAndShareSoldInOfferingPercentage" xlink:to="mbio_PrefundedWarrantAndShareSoldInOfferingPercentage_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_PrefundedWarrantAndShareSoldInOfferingPercentage_lbl" xml:lang="en-US">Percentage of shares and pre-funded warrants sold in the offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_PrefundedWarrantAndShareSoldInOfferingPercentage_lbl" xml:lang="en-US">Prefunded Warrant And Share Sold In Offering, Percentage</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_PrefundedWarrantAndShareSoldInOfferingPercentage_lbl" xml:lang="en-US">Offering percentage sold</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_CombinedOfferingPricePercentage" xlink:label="mbio_CombinedOfferingPricePercentage" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_CombinedOfferingPricePercentage" xlink:to="mbio_CombinedOfferingPricePercentage_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_CombinedOfferingPricePercentage_lbl" xml:lang="en-US">Percentage of combined public offering price per share of common stock and accompanying Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_CombinedOfferingPricePercentage_lbl" xml:lang="en-US">Combined Offering Price, Percentage</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_CombinedOfferingPricePercentage_lbl" xml:lang="en-US">Offering percentage</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ClassOfWarrantOrRightExpiryTerm" xlink:label="mbio_ClassOfWarrantOrRightExpiryTerm" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ClassOfWarrantOrRightExpiryTerm" xlink:to="mbio_ClassOfWarrantOrRightExpiryTerm_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ClassOfWarrantOrRightExpiryTerm_lbl" xml:lang="en-US">Expiry term of warrants, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ClassOfWarrantOrRightExpiryTerm_lbl" xml:lang="en-US">Class of Warrant or Right, Expiry Term</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ClassOfWarrantOrRightExpiryTerm_lbl" xml:lang="en-US">Termination of warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_AtMarketOfferingMember" xlink:label="mbio_AtMarketOfferingMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_AtMarketOfferingMember" xlink:to="mbio_AtMarketOfferingMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_AtMarketOfferingMember_lbl" xml:lang="en-US">Information pertaining to issuances of stock offered on an At The Market basis.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_AtMarketOfferingMember_lbl" xml:lang="en-US">At the Market Offering [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_AtMarketOfferingMember_lbl" xml:lang="en-US">At the Market Offering</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_CommissionRatePercentage" xlink:label="mbio_CommissionRatePercentage" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_CommissionRatePercentage" xlink:to="mbio_CommissionRatePercentage_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_CommissionRatePercentage_lbl" xml:lang="en-US">Percentage of commission rate on gross sale of common stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_CommissionRatePercentage_lbl" xml:lang="en-US">Commission Rate Percentage</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_CommissionRatePercentage_lbl" xml:lang="en-US">Agent commission (as a percent)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="us-gaap_SharesIssuedPricePerShare" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharesIssuedPricePerShare" xlink:to="us-gaap_SharesIssuedPricePerShare_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SharesIssuedPricePerShare_lbl" xml:lang="en-US">Shares Issued, Price Per Share</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SharesIssuedPricePerShare_lbl" xml:lang="en-US">Price per common stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:to="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xml:lang="en-US">Proceeds from Issuance of Common Stock</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xml:lang="en-US">Proceeds from issuance of common shares</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsOfStockIssuanceCosts" xlink:to="us-gaap_PaymentsOfStockIssuanceCosts_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xml:lang="en-US">Payments of Stock Issuance Costs</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xml:lang="en-US">Aggregate fees of stock issuance</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:label="us-gaap_ClassOfWarrantOrRightTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_ClassOfWarrantOrRightTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightTable_lbl" xml:lang="en-US">Class of Warrant or Right [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xml:lang="en-US">Class of Warrant or Right [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xml:lang="en-US">Stockholders' Equity</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod" xlink:label="mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod" xlink:to="mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod_lbl" xml:lang="en-US">The number of warrants or rights exercised and expired during the period.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod_lbl" xml:lang="en-US">Class Of Warrant Or Right, Warrants Exercised And Expired During The Period</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="mbio_ClassOfWarrantOrRightWarrantsExercisedAndExpiredDuringPeriod_lbl" xml:lang="en-US">Warrants Exercised/expired</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_WarrantExercisePriceExpiredDuringPeriod" xlink:label="mbio_WarrantExercisePriceExpiredDuringPeriod" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_WarrantExercisePriceExpiredDuringPeriod" xlink:to="mbio_WarrantExercisePriceExpiredDuringPeriod_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_WarrantExercisePriceExpiredDuringPeriod_lbl" xml:lang="en-US">Warrant exercise price, expired during the period.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_WarrantExercisePriceExpiredDuringPeriod_lbl" xml:lang="en-US">Warrant Exercise Price Expired During Period</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_WarrantExercisePriceExpiredDuringPeriod_lbl" xml:lang="en-US">Weighted Average Exercise Price, Expired (in dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife" xlink:label="mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife" xlink:to="mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife_lbl" xml:lang="en-US">The weighted average remaining contractual life for warrants outstanding.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife_lbl" xml:lang="en-US">Class Of Warrant Or Right Weighted Average Remaining Contractual Life</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_ClassOfWarrantOrRightWeightedAverageRemainingContractualLife_lbl" xml:lang="en-US">Warrants outstanding, remaining contractual life</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember" xlink:label="us-gaap_EmployeeStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeStockMember" xlink:to="us-gaap_EmployeeStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmployeeStockMember_lbl" xml:lang="en-US">Employee Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmployeeStockMember_lbl" xml:lang="en-US">Employee Stock Purchase Plan</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="us-gaap_PlanNameAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PlanNameAxis" xlink:to="us-gaap_PlanNameAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PlanNameAxis_lbl" xml:lang="en-US">Plan Name [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="us-gaap_PlanNameDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PlanNameDomain" xlink:to="us-gaap_PlanNameDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PlanNameDomain_lbl" xml:lang="en-US">Plan Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_EquityIncentivePlanMember" xlink:label="mbio_EquityIncentivePlanMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_EquityIncentivePlanMember" xlink:to="mbio_EquityIncentivePlanMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_EquityIncentivePlanMember_lbl" xml:lang="en-US">Represents information pertaining to equity incentive plan.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_EquityIncentivePlanMember_lbl" xml:lang="en-US">Equity Incentive Plan [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_EquityIncentivePlanMember_lbl" xml:lang="en-US">Incentive Plan</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_lbl" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_lbl" xml:lang="en-US">Shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xml:lang="en-US">Expiration period</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized_lbl" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized_lbl" xml:lang="en-US">Additional shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xml:lang="en-US">Shares available for grant</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:to="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xml:lang="en-US">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xml:lang="en-US">Shares available for future sale</link:label>
    <link:loc xlink:type="locator" xlink:href="tmb-20260331.xsd#mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage" xlink:label="mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage" xlink:to="mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage_lbl" xml:lang="en-US">Employee stock purchase plan, predetermined offering period, lower fair market value percentage.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage_lbl" xml:lang="en-US">Employee Stock Purchase Plan, Predetermined Offering Period, Lower Fair Market Value Percentage</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="mbio_EmployeeStockPurchasePlanPredeterminedOfferingPeriodLowerFairMarketValuePercentage_lbl" xml:lang="en-US">Predetermined offering period, lower fair market value percentage</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeStockOptionMember" xlink:to="us-gaap_EmployeeStockOptionMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xml:lang="en-US">Options</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" xml:lang="en-US">Options rollforward</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" />
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