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  <xs:element id="rnac_NoncashOrPartNoncashReclassificationOfWarrantLiabilityToEquity" abstract="false" name="NoncashOrPartNoncashReclassificationOfWarrantLiabilityToEquity" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ClinicalTrialCostsPolicyTextBlock" abstract="false" name="ClinicalTrialCostsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="rnac_StockIssuedDuringPeriodSharesWarrantReclassificationToEquity" abstract="false" name="StockIssuedDuringPeriodSharesWarrantReclassificationToEquity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_GenovisABMember" abstract="true" name="GenovisABMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ContingentValueRightMember" abstract="true" name="ContingentValueRightMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_TemporaryEquityDisclosureTextBlock" abstract="false" name="TemporaryEquityDisclosureTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="rnac_TemporaryEquitySharesReservedForFutureIssuance" abstract="false" name="TemporaryEquitySharesReservedForFutureIssuance" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_TemporaryEquityPolicyPolicyTextBlock" abstract="false" name="TemporaryEquityPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="rnac_LesseeOperatingLeaseNumberOfOptionsToExtend" abstract="false" name="LesseeOperatingLeaseNumberOfOptionsToExtend" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="rnac_OldCartestianMember" abstract="true" name="OldCartestianMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_AskBioLicenseAgreementMember" abstract="true" name="AskBioLicenseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_A2008Plan2016PlanAnd2018InducementIncentiveAwardPlanMember" abstract="true" name="A2008Plan2016PlanAnd2018InducementIncentiveAwardPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementOfAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementOfAwards" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LicenseAgreementWithShenyangSunshinePharmaceuticalCompanyLimitedMember" abstract="false" name="LicenseAgreementWithShenyangSunshinePharmaceuticalCompanyLimitedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_StockIssuedDuringPeriodSharesWarrantsCanceled" abstract="false" name="StockIssuedDuringPeriodSharesWarrantsCanceled" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_CollaborativeArrangementCostSharePercentage" abstract="false" name="CollaborativeArrangementCostSharePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="rnac_SettlementOfDerivativeLiabilityShares" abstract="false" name="SettlementOfDerivativeLiabilityShares" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" abstract="false" name="ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SOBIPurchaseAgreementMember" abstract="true" name="SOBIPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_StockIssuedDuringWarrantedCanceledPricePerShare" abstract="false" name="StockIssuedDuringWarrantedCanceledPricePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_StockIssuedDuringWarrantedIssuedPricePerShare" abstract="false" name="StockIssuedDuringWarrantedIssuedPricePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_MoscowRussiaLeaseMember" abstract="true" name="MoscowRussiaLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAsset" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_UnderwritingAgreementMember" abstract="true" name="UnderwritingAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_AdjustmentsToAdditionalPaidInCapitalIssuanceOfReplacementOptionsInMerger" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalIssuanceOfReplacementOptionsInMerger" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_StockIssuedDuringWarrantReclassificationToEquityPricePerShare" abstract="false" name="StockIssuedDuringWarrantReclassificationToEquityPricePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_AggregateAmountOfUpfrontAndMilestoneBasedPaymentsPaid" abstract="false" name="AggregateAmountOfUpfrontAndMilestoneBasedPaymentsPaid" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_TemporaryEquityOptionsIssuanceOfReplacementOptionsInMerger" abstract="false" name="TemporaryEquityOptionsIssuanceOfReplacementOptionsInMerger" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementMilestoneReceivable" abstract="false" name="LicenseAndOptionAgreementMilestoneReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_CommonWarrantMember" abstract="true" name="CommonWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_TemporaryEquityStockIssuedDuringPeriodShares" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_CollaborativeArrangementNumberOfSharesIssuedForMilestoneAchievement" abstract="false" name="CollaborativeArrangementNumberOfSharesIssuedForMilestoneAchievement" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsVestedWeightedAverageExercisePrice" abstract="false" name="SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsVestedWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_TemporaryEquityOptionsCarryingAmountAttributableToParent" abstract="false" name="TemporaryEquityOptionsCarryingAmountAttributableToParent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_PreferredStockConvertibleTransactionRestrictionsPercentageOfOriginallyIssuedStockIssuedAndOutstanding" abstract="false" name="PreferredStockConvertibleTransactionRestrictionsPercentageOfOriginallyIssuedStockIssuedAndOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementOfAwardsStockBasedCompensationExpenseRecognizedOnSettlement" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementOfAwardsStockBasedCompensationExpenseRecognizedOnSettlement" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantIncreaseDecrease" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantIncreaseDecrease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_CapitalizedResearchAndExperimentalCostsTaxPurposes" abstract="false" name="CapitalizedResearchAndExperimentalCostsTaxPurposes" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLeaseLiability" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_Dr.TimothyA.SpringerMember" abstract="true" name="Dr.TimothyA.SpringerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_Descartes08ForSLEMember" abstract="true" name="Descartes08ForSLEMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_EmployeeStockPurchasePlan2016Member" abstract="false" name="EmployeeStockPurchasePlan2016Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ContingentValueRightLiabilityPolicyPolicyTextBlock" abstract="false" name="ContingentValueRightLiabilityPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="rnac_CustomerLiabilityRevenueRecognizedIncludingOpeningBalance" abstract="false" name="CustomerLiabilityRevenueRecognizedIncludingOpeningBalance" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SeriesAPreferredStockOptionsMember" abstract="true" name="SeriesAPreferredStockOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_DefinedContributionPlanEmployersMatchingContributionVestingPeriod" abstract="false" name="DefinedContributionPlanEmployersMatchingContributionVestingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_Descartes08ForMGMember" abstract="true" name="Descartes08ForMGMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementClinicalAndCommercialMilestonePaymentExpected" abstract="false" name="LicenseAndOptionAgreementClinicalAndCommercialMilestonePaymentExpected" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ContingentValueRightPercentageOfMilestonePaymentsRoyaltiesAndOtherAmountsToBeDistributed" abstract="false" name="ContingentValueRightPercentageOfMilestonePaymentsRoyaltiesAndOtherAmountsToBeDistributed" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="rnac_GinkgoAgreementMember" abstract="true" name="GinkgoAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_StockIssuedDuringThePeriodValuesCommonStockLicenseAgreement" abstract="false" name="StockIssuedDuringThePeriodValuesCommonStockLicenseAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementMilestonePayments" abstract="false" name="LicenseAndOptionAgreementMilestonePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedOutstandingIntrinsicValue" abstract="false" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedOutstandingIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_A65GroveStreetWatertownMAMember" abstract="true" name="A65GroveStreetWatertownMAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_PrivatePlacementOneMember" abstract="true" name="PrivatePlacementOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_A2019WarrantsMember" abstract="true" name="A2019WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ContingentValueRightLiabilityNoncurrent" abstract="false" name="ContingentValueRightLiabilityNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_ForwardContractToIssueSharesMember" abstract="true" name="ForwardContractToIssueSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementWrittenNoticePeriodBeforeCancellation" abstract="false" name="LicenseAndOptionAgreementWrittenNoticePeriodBeforeCancellation" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_StockIssuedDuringPeriodValueCommonWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodValueCommonWarrantsExercised" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_WarrantsPolicyTextBlock" abstract="false" name="WarrantsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementFutureAdditionalPaymentsExpected" abstract="false" name="LicenseAndOptionAgreementFutureAdditionalPaymentsExpected" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_DeferredTaxAssetsLeasingArrangements" abstract="false" name="DeferredTaxAssetsLeasingArrangements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_OperatingLeaseBaseRent" abstract="false" name="OperatingLeaseBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_FairValueAdjustmentOfContingentValueRightLiability" abstract="false" name="FairValueAdjustmentOfContingentValueRightLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LesseeOperatingLeaseMonthlyBaseRent" abstract="false" name="LesseeOperatingLeaseMonthlyBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LaboratoryEquipmentMember" abstract="false" name="LaboratoryEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledOrSettledInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledOrSettledInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_DecemberTwoThousandNineteenFinancingMember" abstract="true" name="DecemberTwoThousandNineteenFinancingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementRoyaltyPayment" abstract="false" name="LicenseAndOptionAgreementRoyaltyPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_CollaborationAndLicenseAgreementsTextBlock" abstract="false" name="CollaborationAndLicenseAgreementsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="rnac_ReimbursementPercentageBudgetedCostsIncurredToCompleteTheDevelopment" abstract="false" name="ReimbursementPercentageBudgetedCostsIncurredToCompleteTheDevelopment" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="rnac_WarrantsAndRightsOutstandingCurrent" abstract="false" name="WarrantsAndRightsOutstandingCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ClassOfWarrantOrRightWeightedAverageExercisePriceRollForward" abstract="true" name="ClassOfWarrantOrRightWeightedAverageExercisePriceRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_CollaborativeArrangementWrittenNoticePeriodForTermination" abstract="false" name="CollaborativeArrangementWrittenNoticePeriodForTermination" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementSalesMilestonePaymentsThatMayBeReceived" abstract="false" name="LicenseAndOptionAgreementSalesMilestonePaymentsThatMayBeReceived" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SpringerPurchaseAgreementMember" abstract="true" name="SpringerPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_FrederickLeaseAgreementMember" abstract="true" name="FrederickLeaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_TASPartnersLLCMember" abstract="true" name="TASPartnersLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_GinkgoBioworksHoldingsIncMember" abstract="true" name="GinkgoBioworksHoldingsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_ClassOfWarrantOrRightRollForward" abstract="true" name="ClassOfWarrantOrRightRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementOptionTerm" abstract="false" name="LicenseAndOptionAgreementOptionTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_A2017PIPEMember" abstract="true" name="A2017PIPEMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_CollaborativeArrangementPaymentObligation" abstract="false" name="CollaborativeArrangementPaymentObligation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_EmploymentInducementIncentiveAwardPlanMember" abstract="true" name="EmploymentInducementIncentiveAwardPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_AdjustmentsToAdditionalPaidInCapitalDistributionOfContingentValueRights" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalDistributionOfContingentValueRights" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementMilestoneReceivableForCertainDystrophies" abstract="false" name="LicenseAndOptionAgreementMilestoneReceivableForCertainDystrophies" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_EquitySecuritiesStockPurchaseAgreementPurchasePricePerShare" abstract="false" name="EquitySecuritiesStockPurchaseAgreementPurchasePricePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_CollaborativeArrangementSharesIssuedForMilestoneAchievementAmount" abstract="false" name="CollaborativeArrangementSharesIssuedForMilestoneAchievementAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LeaseArrangementAxis" abstract="true" name="LeaseArrangementAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="rnac_A2022WarrantsMember" abstract="true" name="A2022WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_SevenOneEightThreeFourIrrevocableTrustMember" abstract="true" name="SevenOneEightThreeFourIrrevocableTrustMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_NumberOfAcquiredOperatingLeases" abstract="false" name="NumberOfAcquiredOperatingLeases" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="rnac_AccruedResearchAndDevelopmentCostsCurrent" abstract="false" name="AccruedResearchAndDevelopmentCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementUpfrontCashPayment" abstract="false" name="LicenseAndOptionAgreementUpfrontCashPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_WarrantIssued" abstract="false" name="WarrantIssued" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_UpfrontRentalPayment" abstract="false" name="UpfrontRentalPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_StockIssuedDuringThePeriodSharesCommonStockAndWarrants" abstract="false" name="StockIssuedDuringThePeriodSharesCommonStockAndWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_ClassOfWarrantOrRightNumberOfWarrantsExercised" abstract="false" name="ClassOfWarrantOrRightNumberOfWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_ContractwithCustomerLiabilityDeferredRevenue" abstract="false" name="ContractwithCustomerLiabilityDeferredRevenue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_AccruedPatentFeesCurrent" abstract="false" name="AccruedPatentFeesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_DevelopmentAndCommercialMilestonesPlusRoyalties" abstract="false" name="DevelopmentAndCommercialMilestonesPlusRoyalties" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ContingentValueRightLiability" abstract="false" name="ContingentValueRightLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_EquitySecuritiesStockPurchaseAgreementParValuePerShare" abstract="false" name="EquitySecuritiesStockPurchaseAgreementParValuePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="rnac_AdjustmentsToAdditionalPaidInCapitalIssuanceOfCommonStockForwardInConnectionWithTheMerger" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalIssuanceOfCommonStockForwardInConnectionWithTheMerger" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInPeriodWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInPeriodWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="rnac_AstellasGeneTherapiesMember" abstract="true" name="AstellasGeneTherapiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementDevelopmentCostReimbursements" abstract="false" name="LicenseAndOptionAgreementDevelopmentCostReimbursements" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ProbabilityOfSuccessMember" abstract="true" name="ProbabilityOfSuccessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_UnderwritingAgreement2022WarrantsMember" abstract="true" name="UnderwritingAgreement2022WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_EffectiveIncomeTaxRateReconciliationDeferredRevenuePercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeferredRevenuePercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="rnac_A2020TermLoansMember" abstract="true" name="A2020TermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_BiogenM.A.Inc.Member" abstract="true" name="BiogenM.A.Inc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_OldCartesianMember" abstract="true" name="OldCartesianMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherCurrentLiabilities" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherCurrentLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_DeferredTaxAssetsNetOfDeferredTaxLiabilities" abstract="false" name="DeferredTaxAssetsNetOfDeferredTaxLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_StockIssuedDuringThePeriodValuesCommonStockAndWarrants" abstract="false" name="StockIssuedDuringThePeriodValuesCommonStockAndWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_PreFundedWarrantMember" abstract="true" name="PreFundedWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ProceedsFromIssuanceOfCommonStockAndWarrants" abstract="false" name="ProceedsFromIssuanceOfCommonStockAndWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ContractwithCustomerLiabilityDeferredRevenueRevenueRecognized" abstract="false" name="ContractwithCustomerLiabilityDeferredRevenueRevenueRecognized" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_A2022OfferingMember" abstract="true" name="A2022OfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeituresRate" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeituresRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="rnac_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAndDebtSecuritiesAvailableForSale" abstract="false" name="CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAndDebtSecuritiesAvailableForSale" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_PreferredStockConvertibleThresholdConsecutiveTradingDays" abstract="false" name="PreferredStockConvertibleThresholdConsecutiveTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="rnac_AggregateAmountForFuturePaymentsUponAchievementOfClinicalAndRegulatoryApprovalMilestonesForProductsContainingImmTORPlatform" abstract="false" name="AggregateAmountForFuturePaymentsUponAchievementOfClinicalAndRegulatoryApprovalMilestonesForProductsContainingImmTORPlatform" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_November2023PrivatePlacementTrancheThreeMember" abstract="true" name="November2023PrivatePlacementTrancheThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLeaseLiability" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_TakedaAgreementMember" abstract="true" name="TakedaAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_TemporaryEquityOptionsShareBasedPaymentArrangementIncreaseForCostRecognition" abstract="false" name="TemporaryEquityOptionsShareBasedPaymentArrangementIncreaseForCostRecognition" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_TemporaryEquityStockIssuedDuringPeriodAcquisitionsShares" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodAcquisitionsShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_StockIssuedDuringThePeriodSharesCommonStockLicenseAgreement" abstract="false" name="StockIssuedDuringThePeriodSharesCommonStockLicenseAgreement" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_EligiblePeriodToReceiveRoyalties" abstract="false" name="EligiblePeriodToReceiveRoyalties" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_VotesPerShareofCommonStock" abstract="false" name="VotesPerShareofCommonStock" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementExtensionTerm" abstract="false" name="LicenseAndOptionAgreementExtensionTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_CollaborationAndLicenseAgreementsUpfrontPayment" abstract="false" name="CollaborationAndLicenseAgreementsUpfrontPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_CashEquivalentsAndShortTermInvestmentsPolicyTextBlock" abstract="false" name="CashEquivalentsAndShortTermInvestmentsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="rnac_StockIssuedDuringPeriodSharesCommonWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodSharesCommonWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_AdjustmentsToAdditionalPaidInCapitalSettlementOfOutstandingEquityAwards" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalSettlementOfOutstandingEquityAwards" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SareptaTherapeuticsInc.Member" abstract="true" name="SareptaTherapeuticsInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_DebtInstrumentPrepaymentFee" abstract="false" name="DebtInstrumentPrepaymentFee" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledOrSettledWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledOrSettledWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="rnac_SeriesBPreferredStockPurchaseAgreementMember" abstract="true" name="SeriesBPreferredStockPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ContingentValueRightLiabilityDeductionFromDistributionGeneralAndAdministrativeOverhead" abstract="false" name="ContingentValueRightLiabilityDeductionFromDistributionGeneralAndAdministrativeOverhead" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_PrivatePlacementTwoMember" abstract="true" name="PrivatePlacementTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_AccruedInterestCurrent" abstract="false" name="AccruedInterestCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_RevenueNumberOfPerformanceObligations" abstract="false" name="RevenueNumberOfPerformanceObligations" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="rnac_AtTheMarketOfferingMember" abstract="true" name="AtTheMarketOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_PreferredStockConvertibleBeneficialOwnershipPercentage" abstract="false" name="PreferredStockConvertibleBeneficialOwnershipPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="rnac_A704QuinceOrchardRoadLeasesMember" abstract="true" name="A704QuinceOrchardRoadLeasesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_DebtInstrumentAccruedInterest" abstract="false" name="DebtInstrumentAccruedInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_LeaseArrangementDomain" abstract="true" name="LeaseArrangementDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_ContractwithCustomerLiabilityDeferredRevenueIncreaseFromCashReceipts" abstract="false" name="ContractwithCustomerLiabilityDeferredRevenueIncreaseFromCashReceipts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_November2023PrivatePlacementTrancheTwoMember" abstract="true" name="November2023PrivatePlacementTrancheTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_PreferredStockConvertibleRedemptionTermsPeriodFromMerger" abstract="false" name="PreferredStockConvertibleRedemptionTermsPeriodFromMerger" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_StockIssuedDuringPeriodSharesWarrantedIssued" abstract="false" name="StockIssuedDuringPeriodSharesWarrantedIssued" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementDevelopmentMilestone" abstract="false" name="LicenseAndOptionAgreementDevelopmentMilestone" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_PaymentForSettlementOfEquityAwardsInBusinessCombination" abstract="false" name="PaymentForSettlementOfEquityAwardsInBusinessCombination" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ContractwithCustomerLiabilityIncreaseFromCashReceipts" abstract="false" name="ContractwithCustomerLiabilityIncreaseFromCashReceipts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_EffectiveIncomeTaxRateReconciliationChangeInFairValueOfContractLiabilitiesPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationChangeInFairValueOfContractLiabilitiesPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="rnac_ContingentValueRightLiabilityCurrent" abstract="false" name="ContingentValueRightLiabilityCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SaleOfStockSettlementTerm" abstract="false" name="SaleOfStockSettlementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_CyrusBiotechnologyIncMember" abstract="true" name="CyrusBiotechnologyIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="rnac_IncreaseDecreaseInTemporaryEquityOptionRollForwardRollForward" abstract="true" name="IncreaseDecreaseInTemporaryEquityOptionRollForwardRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_OldCartesianPlanMember" abstract="true" name="OldCartesianPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_ProceedFromIssuanceOfCommonStockNet" abstract="false" name="ProceedFromIssuanceOfCommonStockNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ChangeInContractWithCustomerLiabilityRollForward" abstract="true" name="ChangeInContractWithCustomerLiabilityRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="rnac_NationalCancerInstituteAgreementMember" abstract="true" name="NationalCancerInstituteAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_AccruedAuditFeesCurrent" abstract="false" name="AccruedAuditFeesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedOutstandingWeightedAverageRemainingContractualTerm" abstract="false" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedOutstandingWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_EquitySecuritiesStockPurchaseAgreementSharesPurchased" abstract="false" name="EquitySecuritiesStockPurchaseAgreementSharesPurchased" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="rnac_SecuritiesPurchaseAgreementMember" abstract="true" name="SecuritiesPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_November2023PrivatePlacementTrancheOneMember" abstract="true" name="November2023PrivatePlacementTrancheOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_LicenseAndOptionAgreementBenchmarkRoyaltiesMaximum" abstract="false" name="LicenseAndOptionAgreementBenchmarkRoyaltiesMaximum" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_TemporaryEquityStockIssuedDuringPeriodAcquisitionsValue" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodAcquisitionsValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_ContingentValueRightLiabilityMeasurementInput" abstract="false" name="ContingentValueRightLiabilityMeasurementInput" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:decimalItemType"/>
  <xs:element id="rnac_WarrantsAndRightsOutstandingNoncurrent" abstract="false" name="WarrantsAndRightsOutstandingNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="rnac_PreferredStockRedemptionTerm" abstract="false" name="PreferredStockRedemptionTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="rnac_ShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementOfAwardsAmount" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSettlementOfAwardsAmount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="rnac_November2023PrivatePlacementMember" abstract="true" name="November2023PrivatePlacementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="rnac_SaleofStockPercentageOfTenDayVolumeWeightedAveragePriceOfCommonStock" abstract="false" name="SaleofStockPercentageOfTenDayVolumeWeightedAveragePriceOfCommonStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="rnac_NoncashOrPartNoncashWarrantExercises" abstract="false" name="NoncashOrPartNoncashWarrantExercises" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
