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  <xs:element id="allo_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" abstract="false" name="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_LesseeOperatingLeaseOptionToExtendNumber" abstract="false" name="LesseeOperatingLeaseOptionToExtendNumber" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="allo_NewarkMember" abstract="true" name="NewarkMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_JointVentureCapitalSupportPayments" abstract="false" name="JointVentureCapitalSupportPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_LeaseTwoMember" abstract="true" name="LeaseTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_BellcoCapitalLLCMember" abstract="true" name="BellcoCapitalLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_LeaseOneMember" abstract="true" name="LeaseOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_AllogeneOverlandMember" abstract="true" name="AllogeneOverlandMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_AllogeneOverlandAllogeneOverlandBioPharmHKLimitedMember" abstract="true" name="AllogeneOverlandAllogeneOverlandBioPharmHKLimitedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_FounderSharesOfCommonStockMember" abstract="true" name="FounderSharesOfCommonStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_StockIssuanceMaximumCompensationDueToThirdPartyPercent" abstract="false" name="StockIssuanceMaximumCompensationDueToThirdPartyPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_ExpectedSharesPurchasedUnderEmployeeStockPurchasePlanMember" abstract="true" name="ExpectedSharesPurchasedUnderEmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_TransitionServicesAgreementMember" abstract="true" name="TransitionServicesAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_PaymentsCommencingJanuary2020Member" abstract="true" name="PaymentsCommencingJanuary2020Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_RelatedPartyTransactionCompensationPercentage" abstract="false" name="RelatedPartyTransactionCompensationPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_AccruedResearchAndDevelopmentCostsPolicyTextBlock" abstract="false" name="AccruedResearchAndDevelopmentCostsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="allo_OptionExercisePriceAsPercentageOfFairValueOfCommonStockOnGrateDate1" abstract="false" name="OptionExercisePriceAsPercentageOfFairValueOfCommonStockOnGrateDate1" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedWeightedAverageRemainingContractualTerms" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedWeightedAverageRemainingContractualTerms" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="allo_TaxExpiration2037Member" abstract="true" name="TaxExpiration2037Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_UnvestedSharesLiabilitiesCurrent" abstract="false" name="UnvestedSharesLiabilitiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_NorthAmericaEuropeAsiaAustraliaAndOceaniaMember" abstract="true" name="NorthAmericaEuropeAsiaAustraliaAndOceaniaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_IndefiniteMember" abstract="true" name="IndefiniteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_PercentageOfEligibleCompensationContributionByEmployee" abstract="false" name="PercentageOfEligibleCompensationContributionByEmployee" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_ResearchCollaborationAndLicenseAgreementMember" abstract="true" name="ResearchCollaborationAndLicenseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_ShorttermLeaseRentExpense" abstract="false" name="ShorttermLeaseRentExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="allo_OptionExercisePriceAsPercentageOfFairValueOfCommonStockOnGrateDate" abstract="false" name="OptionExercisePriceAsPercentageOfFairValueOfCommonStockOnGrateDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_CostMethodInvestmentTransactionCosts" abstract="false" name="CostMethodInvestmentTransactionCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_AvailableForSaleSecuritiesDebtMaturitiesWithinThreeYearFairValue" abstract="false" name="AvailableForSaleSecuritiesDebtMaturitiesWithinThreeYearFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_ClinicalRegulatoryAndCommercialMilestoneMember" abstract="true" name="ClinicalRegulatoryAndCommercialMilestoneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_PercentageOfDevelopmentCostTheCompanyIsResponsibleFor" abstract="false" name="PercentageOfDevelopmentCostTheCompanyIsResponsibleFor" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_LiabilitiesLesseeTableTextBlock" abstract="false" name="LiabilitiesLesseeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="allo_TwoThousandEighteenEmployeeStockPurchasePlanMember" abstract="true" name="TwoThousandEighteenEmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_DeferredTaxLiabilitiesRightOfUseLeased" abstract="false" name="DeferredTaxLiabilitiesRightOfUseLeased" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_TwoRiverConsultingLimitedLiabiltyCompanyMember" abstract="true" name="TwoRiverConsultingLimitedLiabiltyCompanyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_PurchaseOfCommonStockThroughPayrollDeductionsToEqualPriceOfLowerFairMarketValue" abstract="false" name="PurchaseOfCommonStockThroughPayrollDeductionsToEqualPriceOfLowerFairMarketValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_CapitalizedCosts" abstract="false" name="CapitalizedCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_AggregatePotentialMilestonePayments" abstract="false" name="AggregatePotentialMilestonePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_CombinedVotingPowerByIndividual" abstract="false" name="CombinedVotingPowerByIndividual" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="allo_CurrentOfferingPeriod" abstract="false" name="CurrentOfferingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="allo_DenominatorAbstract" abstract="true" name="DenominatorAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="allo_FoundersMember" abstract="true" name="FoundersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_VotingInterestMember" abstract="true" name="VotingInterestMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_AccruedCompensationAndRelatedBenefitsCurrent" abstract="false" name="AccruedCompensationAndRelatedBenefitsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_EstimatedLifeOfAssetsTableTextBlock" abstract="false" name="EstimatedLifeOfAssetsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="allo_OtherCurrentAssets" abstract="false" name="OtherCurrentAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="allo_AssetContributionAgreementMember" abstract="true" name="AssetContributionAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="allo_ByHeartMember" abstract="true" name="ByHeartMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
