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  <xsd:element id="cadl_NonRefundableFee" name="NonRefundableFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_IPOIncludingUnderwritersOverallotmentOptionMember" name="IPOIncludingUnderwritersOverallotmentOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_LoanAgreementMember" name="LoanAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_ManufacturingEquipmentMember" name="ManufacturingEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_StockOptionsOutstandingMember" name="StockOptionsOutstandingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_PaymentForLicenseFee" name="PaymentForLicenseFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_PastServicesProvidedByBeneficiary" name="PastServicesProvidedByBeneficiary" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_UnauditedInterimFinancialInformationPolicyTextBlock" name="UnauditedInterimFinancialInformationPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_OrganizationAndBasisOfPresentationLineItems" name="OrganizationAndBasisOfPresentationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_ScheduleOfCommonStockReservedForFutureIssuanceTableTextBlock" name="ScheduleOfCommonStockReservedForFutureIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_MaximumAmountUponAchievementOfVariousClinicalCommercialAndSalesMilestones" name="MaximumAmountUponAchievementOfVariousClinicalCommercialAndSalesMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cadl_CommittedPeriodToRemittingInSupportOfClinicalTrial" name="CommittedPeriodToRemittingInSupportOfClinicalTrial" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_ClassOfWarrantOrRightConsecutiveTradingDays1" name="ClassOfWarrantOrRightConsecutiveTradingDays1" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_UpfrontLicenseFee" name="UpfrontLicenseFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_TwoThousandFifteenStockPlanMember" name="TwoThousandFifteenStockPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_NumberOfProductCandidates" name="NumberOfProductCandidates" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionUnvestedWeightedAverageRemainingContractual" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionUnvestedWeightedAverageRemainingContractual" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_SharesAvailableForFutureGrantUnderStockOptionPlanMember" name="SharesAvailableForFutureGrantUnderStockOptionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_PercentageIncomeTaxesBenefitsUponUltimateSettlement" name="PercentageIncomeTaxesBenefitsUponUltimateSettlement" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_SeriesBConditionalWarrantsMember" name="SeriesBConditionalWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_DueFromRelatedParty" name="DueFromRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cadl_SeriesBPreferredAsConvertedToCommonStockMember" name="SeriesBPreferredAsConvertedToCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_AccruedInterestDueUponMaturityPeriod" name="AccruedInterestDueUponMaturityPeriod" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_ExpectedDividendAssumed" name="ExpectedDividendAssumed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_PaymentAtTimeOfEnteringIntoLicense" name="PaymentAtTimeOfEnteringIntoLicense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_WarrantLiabilityNoncurrent" name="WarrantLiabilityNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_PatentCostsPolicyTextBlock" name="PatentCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_CommonStockCapitalSharesReservedForFutureIssuanceDescriptions" name="CommonStockCapitalSharesReservedForFutureIssuanceDescriptions" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_ShareBasedCompensationAwardTrancheFourMember" name="ShareBasedCompensationAwardTrancheFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_ScheduleOfOtherInformationRelatedToOperatingLeasesTableTextBlock" name="ScheduleOfOtherInformationRelatedToOperatingLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_TechnologyLicenseAgreementLineItems" name="TechnologyLicenseAgreementLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_BrighamAndWomensHospitalIncLicenseAgreementMember" name="BrighamAndWomensHospitalIncLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_SeriesAWarrantsMember" name="SeriesAWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_BusinessAcquisitionPresentValueOfFutureCashOutflow" name="BusinessAcquisitionPresentValueOfFutureCashOutflow" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_NumberOfConsecutiveInstallments" name="NumberOfConsecutiveInstallments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_ExclusiveLicensingAgreementMember" name="ExclusiveLicensingAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_OrganizationAndBasisOfPresentationTable" name="OrganizationAndBasisOfPresentationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_MarketableDebtSecuritiesMaturitiesDuration" name="MarketableDebtSecuritiesMaturitiesDuration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_StockIssuedDuringPeriodValueWarrantExercised" name="StockIssuedDuringPeriodValueWarrantExercised" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_InterestIncome" name="InterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_ClassOfWarrantOrRightExerciseAverageMarketPricePerShare" name="ClassOfWarrantOrRightExerciseAverageMarketPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cadl_IncreaseDecreaseInDeferredRent" name="IncreaseDecreaseInDeferredRent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cadl_ClassOfWarrantOrRightPeriod" name="ClassOfWarrantOrRightPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_PaycheckProtectionProgramLoanForgiveness" name="PaycheckProtectionProgramLoanForgiveness" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_SeriesBWarrantLiabilityMember" name="SeriesBWarrantLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_GovernmentGrantsPolicyTextBlock" name="GovernmentGrantsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_EstimatedMarketRateForUnsecuredLoan" name="EstimatedMarketRateForUnsecuredLoan" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cadl_BusinessAcquisitionCarryingValueOfPromissoryNote" name="BusinessAcquisitionCarryingValueOfPromissoryNote" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_AtTheMarketOfferingMember" name="AtTheMarketOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_PublicFloatIssuingSecurities" name="PublicFloatIssuingSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_FuturePaymentMadeUponTheAchievementOfSales" name="FuturePaymentMadeUponTheAchievementOfSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_MeasurementInputCreditRateMember" name="MeasurementInputCreditRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_NonCashLeaseExpense" name="NonCashLeaseExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cadl_OutstandingWarrantsForCommonStockMember" name="OutstandingWarrantsForCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_ClassOfWarrantOrRightIssued" name="ClassOfWarrantOrRightIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cadl_DebtInstrumentAccretionOfDebtDiscount" name="DebtInstrumentAccretionOfDebtDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_TwoThousandTwentyOneEquityIncentivePlanMember" name="TwoThousandTwentyOneEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_AggregateExercisePriceOfCommonStockShares" name="AggregateExercisePriceOfCommonStockShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_NoncancelableOperatingLeaseExpirationDate" name="NoncancelableOperatingLeaseExpirationDate" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_DebtInstrumentFinalPaymentFee" name="DebtInstrumentFinalPaymentFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_CommonStockExchangeForOptionExercise" name="CommonStockExchangeForOptionExercise" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cadl_PromissoryNoteContractualInterestRate" name="PromissoryNoteContractualInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cadl_CommercialPurposesAtPriceOfCostPlusPercentage" name="CommercialPurposesAtPriceOfCostPlusPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_NonCashInterestExpense" name="NonCashInterestExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cadl_NCOhioTrustWarrantsMember" name="NCOhioTrustWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_AccountingStandardsUpdate202005Member" name="AccountingStandardsUpdate202005Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cadl_PaymentForAnnualLicenseFee" name="PaymentForAnnualLicenseFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cadl_EmergingGrowthCompanyPolicyTextBlock" name="EmergingGrowthCompanyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_ClassOfWarrantOrRightExtendedExpirationDates" name="ClassOfWarrantOrRightExtendedExpirationDates" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_ClassOfWarrantOrRightExercisePricePerShare" name="ClassOfWarrantOrRightExercisePricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cadl_LongTermDebtDueMonthAndYear" name="LongTermDebtDueMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cadl_DebtInstrumentFinalPaymentFeePercentage" name="DebtInstrumentFinalPaymentFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
