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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/EquityQ1Tables" id="EquityQ1Tables">
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        <link:definition>111100 - Disclosure - Equity (Q1) (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>112300 - Disclosure - Merger (FY) (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>112600 - Disclosure - Fair Value Measurements (FY) (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/PropertyAndEquipmentFyTables" id="PropertyAndEquipmentFyTables">
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        <link:definition>112700 - Disclosure - Property and Equipment (FY) (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/LeasesFyTables" id="LeasesFyTables">
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        <link:definition>112900 - Disclosure - Leases (FY) (Tables)</link:definition>
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        <link:definition>113100 - Disclosure - Series A Preferred Stock (FY) (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/EquityFyTables" id="EquityFyTables">
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        <link:definition>113200 - Disclosure - Equity (FY) (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:definition>113300 - Disclosure - Stock Incentive Plans (FY) (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>113400 - Disclosure - Revenue Arrangements (FY) (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/RelatedpartyTransactionsFyTables" id="RelatedpartyTransactionsFyTables">
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        <link:definition>114000 - Disclosure - Restructuring (FY) (Tables)</link:definition>
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        <!--Parent Role: Description of the Business (Q1)-->
        <link:definition>120100 - Disclosure - Description of the Business (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Merger (Q1)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>120302 - Disclosure - Merger - Schedule of Fair Value of Consideration (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/MergerScheduleOfAssetsAcquiredAndLiabilitiesAssumedQ1Details" id="MergerScheduleOfAssetsAcquiredAndLiabilitiesAssumedQ1Details">
        <!--Parent Role: Merger (Q1)-->
        <link:definition>120304 - Disclosure - Merger - Schedule of Assets Acquired and Liabilities Assumed (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/MergerScheduleOfIntangibleAssetsAcquiredQ1Details" id="MergerScheduleOfIntangibleAssetsAcquiredQ1Details">
        <!--Parent Role: Merger (Q1)-->
        <link:definition>120306 - Disclosure - Merger - Schedule of Intangible Assets Acquired (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Net Loss Per Share (Q1)-->
        <link:definition>120400 - Disclosure - Net Loss Per Share - Computation of Basic and Diluted Net Loss Per Share (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Net Loss Per Share (Q1)-->
        <link:definition>120402 - Disclosure - Net Loss Per Share - Schedule of Potential Common Shares Issuable Upon Conversion of Warrants (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>120500 - Disclosure - Fair Value Measurements - Schedule of Assets Measured at Fair Value on a Recurring Basis (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/FairValueMeasurementsNarrativeQ1Details" id="FairValueMeasurementsNarrativeQ1Details">
        <!--Parent Role: Fair Value Measurements (Q1)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Fair Value Measurements (Q1)-->
        <link:definition>120504 - Disclosure - Fair Value Measurements - Schedule of Cash and Cash Equivalents (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/FairValueMeasurementsAssumptionsUsedToRecordFairValueOfWarrantsQ1Details" id="FairValueMeasurementsAssumptionsUsedToRecordFairValueOfWarrantsQ1Details">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/FairValueMeasurementsChangeInWarrantLiabilitiesQ1Details" id="FairValueMeasurementsChangeInWarrantLiabilitiesQ1Details">
        <!--Parent Role: Fair Value Measurements (Q1)-->
        <link:definition>120508 - Disclosure - Fair Value Measurements - Change in the Warrant Liabilities (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/FairValueMeasurementsScheduleOfSignificantInputsUsedToEstimateFairValueOfCvrsQ1Details" id="FairValueMeasurementsScheduleOfSignificantInputsUsedToEstimateFairValueOfCvrsQ1Details">
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        <link:definition>120510 - Disclosure - Fair Value Measurements - Schedule of Significant Inputs Used to Estimate the Fair Value of the CVRs (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/FairValueMeasurementsChangeInForwardContractLiabilitiesQ1Details" id="FairValueMeasurementsChangeInForwardContractLiabilitiesQ1Details">
        <!--Parent Role: Fair Value Measurements (Q1)-->
        <link:definition>120512 - Disclosure - Fair Value Measurements - Change in the Forward Contract Liabilities (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/PropertyAndEquipmentScheduleOfPropertyAndEquipmentQ1Details" id="PropertyAndEquipmentScheduleOfPropertyAndEquipmentQ1Details">
        <!--Parent Role: Property and Equipment (Q1)-->
        <link:definition>120600 - Disclosure - Property and Equipment - Schedule of Property and Equipment (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/PropertyAndEquipmentNarrativeQ1Details" id="PropertyAndEquipmentNarrativeQ1Details">
        <!--Parent Role: Property and Equipment (Q1)-->
        <link:definition>120602 - Disclosure - Property and Equipment - Narrative (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/AccruedExpensesQ1Details" id="AccruedExpensesQ1Details">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/LeasesNarrativeQ1Details" id="LeasesNarrativeQ1Details">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/LeasesComponentsOfLeaseCostsQ1Details" id="LeasesComponentsOfLeaseCostsQ1Details">
        <!--Parent Role: Leases (Q1)-->
        <link:definition>120802 - Disclosure - Leases - Components of Lease Costs (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/LeasesOperatingLeaseLiabilityMaturityQ1Details" id="LeasesOperatingLeaseLiabilityMaturityQ1Details">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>120806 - Disclosure - Leases - Operating Lease, Liability, Maturity (Q1) (Details) CALC 01</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/LeasesLeaseTermAndDiscountRateQ1Details" id="LeasesLeaseTermAndDiscountRateQ1Details">
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        <link:definition>120808 - Disclosure - Leases - Lease Term and Discount Rate (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/DebtQ1Details" id="DebtQ1Details">
        <!--Parent Role: Debt (Q1)-->
        <link:definition>120900 - Disclosure - Debt (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://selectabio.com/role/SeriesPreferredStockQ1Details" id="SeriesPreferredStockQ1Details">
        <!--Parent Role: Series A Preferred Stock (Q1)-->
        <link:definition>121000 - Disclosure - Series A Preferred Stock (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <!--Parent Role: Equity (Q1)-->
        <link:definition>121100 - Disclosure - Equity - Narrative (Q1) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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  <xs:element name="CollaborationAndLicenseAgreementsUpfrontPayment" id="rnac_CollaborationAndLicenseAgreementsUpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
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  <xs:element name="CommonStockSharesOutstandingProFormaIfPreferredStockConverted" id="rnac_CommonStockSharesOutstandingProFormaIfPreferredStockConverted" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" />
  <xs:element name="LesseeOperatingLeaseBaseRentAnnualUpwardAdjustmentPercentageAfterYearOne" id="rnac_LesseeOperatingLeaseBaseRentAnnualUpwardAdjustmentPercentageAfterYearOne" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="ConvertiblePreferredStockSharesThatDidNotAutomaticallyConvert" id="rnac_ConvertiblePreferredStockSharesThatDidNotAutomaticallyConvert" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="LesseeOperatingLeaseAdditionalAnnualBaseRentYearOne" id="rnac_LesseeOperatingLeaseAdditionalAnnualBaseRentYearOne" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="NumberOfBusinessDays" id="rnac_NumberOfBusinessDays" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" />
  <xs:element name="BeneficialOwnershipLimitationPercentageForConversionOfCommonStockIssuedAndOutstanding" id="rnac_BeneficialOwnershipLimitationPercentageForConversionOfCommonStockIssuedAndOutstanding" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" />
  <xs:element name="ContractWithCustomerMilestonePaymentsReceived" id="rnac_ContractWithCustomerMilestonePaymentsReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" id="rnac_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
</xs:schema>
