<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019d6d72-b242-79ed-97c9-cc91e4b2fc02,g:7d71bdc4-e439-48dd-a8a2-8474147117a0-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel"/>
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableOptionAwardsMember_label_en-US" xlink:label="lab_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableOptionAwardsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table, Option Awards [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableOptionAwardsMember" xlink:href="cbus-20260420.xsd#cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableOptionAwardsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableOptionAwardsMember" xlink:to="lab_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableOptionAwardsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_EquityAwardsExcessFairValueFromModificationsMember_label_en-US" xlink:label="lab_cbus_EquityAwardsExcessFairValueFromModificationsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Awards, Excess Fair Value from Modifications [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_EquityAwardsExcessFairValueFromModificationsMember" xlink:href="cbus-20260420.xsd#cbus_EquityAwardsExcessFairValueFromModificationsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_EquityAwardsExcessFairValueFromModificationsMember" xlink:to="lab_cbus_EquityAwardsExcessFairValueFromModificationsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProfitLoss_label_en-US" xlink:label="lab_us-gaap_ProfitLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProfitLoss" xlink:to="lab_us-gaap_ProfitLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_JasonStokesEsq.Member_label_en-US" xlink:label="lab_cbus_JasonStokesEsq.Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Jason Stokes, Esq. [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_JasonStokesEsq.Member" xlink:href="cbus-20260420.xsd#cbus_JasonStokesEsq.Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_JasonStokesEsq.Member" xlink:to="lab_cbus_JasonStokesEsq.Member" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_PeterBeethamMember_label_en-US" xlink:label="lab_cbus_PeterBeethamMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Peter Beetham [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_PeterBeethamMember" xlink:href="cbus-20260420.xsd#cbus_PeterBeethamMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_PeterBeethamMember" xlink:to="lab_cbus_PeterBeethamMember" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_GregGocalPh.D.Member_label_en-US" xlink:label="lab_cbus_GregGocalPh.D.Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Greg Gocal, Ph.D. [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_GregGocalPh.D.Member" xlink:href="cbus-20260420.xsd#cbus_GregGocalPh.D.Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_GregGocalPh.D.Member" xlink:to="lab_cbus_GregGocalPh.D.Member" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableStockAwardsMember_label_en-US" xlink:label="lab_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableStockAwardsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table, Stock Awards [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableStockAwardsMember" xlink:href="cbus-20260420.xsd#cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableStockAwardsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableStockAwardsMember" xlink:to="lab_cbus_AggregateGrantDateFairValueOfEquityAwardAmountsReportedInSummaryCompensationTableStockAwardsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_MichaelCarrMember_label_en-US" xlink:label="lab_cbus_MichaelCarrMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Michael Carr [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_MichaelCarrMember" xlink:href="cbus-20260420.xsd#cbus_MichaelCarrMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_MichaelCarrMember" xlink:to="lab_cbus_MichaelCarrMember" xlink:type="arc" order="1"/>
    <link:label id="lab_cbus_RoryRiggsMember_label_en-US" xlink:label="lab_cbus_RoryRiggsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Rory Riggs [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_cbus_RoryRiggsMember" xlink:href="cbus-20260420.xsd#cbus_RoryRiggsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cbus_RoryRiggsMember" xlink:to="lab_cbus_RoryRiggsMember" xlink:type="arc" order="1"/>
  </link:labelLink>
</link:linkbase>
