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<!--Generated by DFIN XBRL Instance Document - http://www.dfinsolutions.com/ - Version R3.0 - on 29-June-2026 [08:56:20] {PM}-->
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_EquitySecuritiesRiskMember" xml:lang="en-US">Equity securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_EquitySecuritiesRiskMember" xlink:to="lab_jhit_EquitySecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_ESGintegrationriskMember" xlink:label="loc_jhit_ESGintegrationriskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_ESGintegrationriskMember" xml:lang="en-US">ESG integration risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_ESGintegrationriskMember" xlink:to="lab_jhit_ESGintegrationriskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_FixedIncomeSecuritiesRiskMember" xlink:label="loc_jhit_FixedIncomeSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_FixedIncomeSecuritiesRiskMember" xml:lang="en-US">Fixed income securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_FixedIncomeSecuritiesRiskMember" xlink:to="lab_jhit_FixedIncomeSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_ForeignSecuritiesRiskMember" xlink:label="loc_jhit_ForeignSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_ForeignSecuritiesRiskMember" xml:lang="en-US">Foreign securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_ForeignSecuritiesRiskMember" xlink:to="lab_jhit_ForeignSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_HedgingDerivativesAndOtherStrategicTransactionsRiskMember" xlink:label="loc_jhit_HedgingDerivativesAndOtherStrategicTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_HedgingDerivativesAndOtherStrategicTransactionsRiskMember" xml:lang="en-US">Hedging, derivatives, and other strategic transactions risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_HedgingDerivativesAndOtherStrategicTransactionsRiskMember" xlink:to="lab_jhit_HedgingDerivativesAndOtherStrategicTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_IlliquidAndRestrictedSecuritiesRiskMember" xlink:label="loc_jhit_IlliquidAndRestrictedSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_IlliquidAndRestrictedSecuritiesRiskMember" xml:lang="en-US">Illiquid and restricted securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_IlliquidAndRestrictedSecuritiesRiskMember" xlink:to="lab_jhit_IlliquidAndRestrictedSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_LeveragingRiskMember" xlink:label="loc_jhit_LeveragingRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_LeveragingRiskMember" xml:lang="en-US">Leveraging risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_LeveragingRiskMember" xlink:to="lab_jhit_LeveragingRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_LiquidityRiskMember" xlink:label="loc_jhit_LiquidityRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_LiquidityRiskMember" xml:lang="en-US">Liquidity risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_LiquidityRiskMember" xlink:to="lab_jhit_LiquidityRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" xlink:label="loc_jhit_LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" xml:lang="en-US">Lower rated and high yield fixed income securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" xlink:to="lab_jhit_LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_MortgageBackedAndAssetBackedSecuritiesRiskMember" xlink:label="loc_jhit_MortgageBackedAndAssetBackedSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_MortgageBackedAndAssetBackedSecuritiesRiskMember" xml:lang="en-US">Mortgage backed and asset backed securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_MortgageBackedAndAssetBackedSecuritiesRiskMember" xlink:to="lab_jhit_MortgageBackedAndAssetBackedSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_OperationalandcybersecurityRiskMember" xlink:label="loc_jhit_OperationalandcybersecurityRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_OperationalandcybersecurityRiskMember" xml:lang="en-US">Operational and cybersecurity Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_OperationalandcybersecurityRiskMember" xlink:to="lab_jhit_OperationalandcybersecurityRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_PreferredAndConvertibleSecuritiesRiskMember" xlink:label="loc_jhit_PreferredAndConvertibleSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_PreferredAndConvertibleSecuritiesRiskMember" xml:lang="en-US">Preferred and convertible securities risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_PreferredAndConvertibleSecuritiesRiskMember" xlink:to="lab_jhit_PreferredAndConvertibleSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_USGovernmentagencyobligationsriskMember" xlink:label="loc_jhit_USGovernmentagencyobligationsriskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_USGovernmentagencyobligationsriskMember" xml:lang="en-US">U S Government agency obligations risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_USGovernmentagencyobligationsriskMember" xlink:to="lab_jhit_USGovernmentagencyobligationsriskMember" />
          <link:loc xlink:type="locator" xlink:href="jhit-20260430.xsd#jhit_Note1Member" xlink:label="loc_jhit_Note1Member" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_jhit_Note1Member" xml:lang="en-US">Note 1 [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_jhit_Note1Member" xlink:to="lab_jhit_Note1Member" />
        </link:labelLink>
      </link:linkbase>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <import namespace="http://xbrl.sec.gov/cef/2025" schemaLocation="https://xbrl.sec.gov/cef/2025/cef-2025.xsd" />
  <import namespace="http://xbrl.sec.gov/cef-pre/2025" schemaLocation="https://xbrl.sec.gov/cef/2025/cef-2025_pre.xsd" />
  <element name="Note1Member" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_Note1Member" substitutionGroup="xbrli:item" />
  <element name="ChangingDistributionLevelAndReturnOfCapitalRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_ChangingDistributionLevelAndReturnOfCapitalRiskMember" substitutionGroup="xbrli:item" />
  <element name="CreditAndCounterpartyRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_CreditAndCounterpartyRiskMember" substitutionGroup="xbrli:item" />
  <element name="EconomicAndMarketEventsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_EconomicAndMarketEventsRiskMember" substitutionGroup="xbrli:item" />
  <element name="EquitySecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_EquitySecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ESGintegrationriskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_ESGintegrationriskMember" substitutionGroup="xbrli:item" />
  <element name="FixedIncomeSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_FixedIncomeSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ForeignSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_ForeignSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="HedgingDerivativesAndOtherStrategicTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_HedgingDerivativesAndOtherStrategicTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="IlliquidAndRestrictedSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_IlliquidAndRestrictedSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="LeveragingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_LeveragingRiskMember" substitutionGroup="xbrli:item" />
  <element name="LiquidityRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_LiquidityRiskMember" substitutionGroup="xbrli:item" />
  <element name="LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_LowerRatedAndHighYieldFixedIncomeSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="MortgageBackedAndAssetBackedSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_MortgageBackedAndAssetBackedSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="OperationalandcybersecurityRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_OperationalandcybersecurityRiskMember" substitutionGroup="xbrli:item" />
  <element name="PreferredAndConvertibleSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_PreferredAndConvertibleSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="USGovernmentagencyobligationsriskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="jhit_USGovernmentagencyobligationsriskMember" substitutionGroup="xbrli:item" />
</schema>
