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  <xsd:element id="nktx_TemporaryEquityPreferredStockPurchaseRightLiabilityReversalUponIssuanceOfConvertibleSecurities" name="TemporaryEquityPreferredStockPurchaseRightLiabilityReversalUponIssuanceOfConvertibleSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="nktx_TemporaryEquityReacquisitionOfBeneficialConversionFeatureUponSettlementOfPromissoryNotes" name="TemporaryEquityReacquisitionOfBeneficialConversionFeatureUponSettlementOfPromissoryNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="nktx_TemporaryEquityReclassificationOfPreferredStockPurchaseRightLiabilityToEquityUponIssuanceOfConvertiblePreferredStock" name="TemporaryEquityReclassificationOfPreferredStockPurchaseRightLiabilityToEquityUponIssuanceOfConvertiblePreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="nktx_TemporaryEquityStockIssuableUponAchievementOfMilestone" name="TemporaryEquityStockIssuableUponAchievementOfMilestone" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_TemporaryEquityStockIssuedDuringPeriodSharesUponConversionOfPromissoryNotes" name="TemporaryEquityStockIssuedDuringPeriodSharesUponConversionOfPromissoryNotes" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_TemporaryEquityStockIssuedDuringPeriodValueUponConversionOfPromissoryNotes" name="TemporaryEquityStockIssuedDuringPeriodValueUponConversionOfPromissoryNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="nktx_TenantImprovementsYetToReceiveFromLessor" name="TenantImprovementsYetToReceiveFromLessor" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="nktx_UnrecognizedTaxBenefitsIncreasesDecreasesResultingFromPriorPeriodTaxPositions" name="UnrecognizedTaxBenefitsIncreasesDecreasesResultingFromPriorPeriodTaxPositions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="nktx_WeightedAverageNumberOfSharesUnvestedCommonStockIssuedUponEarlyExerciseOfCommonStockOptions" name="WeightedAverageNumberOfSharesUnvestedCommonStockIssuedUponEarlyExerciseOfCommonStockOptions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_AccountingPoliciesLineItems" name="AccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_AfterYearTwoMember" name="AfterYearTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_AgreementWithFinancialInstitutionMember" name="AgreementWithFinancialInstitutionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_AtMarketProgramMember" name="AtMarketProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_CarryForwardIndefinitelyMember" name="CarryForwardIndefinitelyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_CollaborationAndLicenseAgreementMember" name="CollaborationAndLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_CommonStockOptionsMember" name="CommonStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_ComputersAndSoftwareMember" name="ComputersAndSoftwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_CorporateOfficeAndLaboratoryFacilitiesMember" name="CorporateOfficeAndLaboratoryFacilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_CorporateOfficeAndLaboratorySpaceMember" name="CorporateOfficeAndLaboratorySpaceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_DevelopmentAndRegulatoryApprovalMilestonesMember" name="DevelopmentAndRegulatoryApprovalMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_ExpirationYearOneMember" name="ExpirationYearOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_ExpirationYearTwoMember" name="ExpirationYearTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_GlaxoSmithKlineConvertibleNoteMember" name="GlaxoSmithKlineConvertibleNoteMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_GlaxoSmithKlineIntellectualPropertyDevelopmentLimitedAndGlaxoGroupLimitedMember" name="GlaxoSmithKlineIntellectualPropertyDevelopmentLimitedAndGlaxoGroupLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_InitialLeaseAgreementMember" name="InitialLeaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_KPlanMember" name="KPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_LicenseAgreementMember" name="LicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_MaxcyteLicenseAgreementMember" name="MaxcyteLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_NationalUniversityOfSingaporeAndStJudeChildrenSResearchHospitalMember" name="NationalUniversityOfSingaporeAndStJudeChildrenSResearchHospitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_NetOperatingLossAndTaxCreditCarryforwardsToOffsetMember" name="NetOperatingLossAndTaxCreditCarryforwardsToOffsetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_NkCellProductsMember" name="NkCellProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_ResearchCollaborationAgreementMember" name="ResearchCollaborationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_ResearchEquipmentMember" name="ResearchEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_SeparationAndReleaseAgreementMember" name="SeparationAndReleaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_SeriesAConvertiblePreferredStockMember" name="SeriesAConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_SeriesAFinancingInvestorsMember" name="SeriesAFinancingInvestorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_SeriesAInvestorsMember" name="SeriesAInvestorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_SeriesBConvertiblePromissoryNotesMember" name="SeriesBConvertiblePromissoryNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_StockPurchaseAgreementMember" name="StockPurchaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_ThirdAmendmentMember" name="ThirdAmendmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_TwoThousandFifteenEquityIncentivePlanMember" name="TwoThousandFifteenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_TwoThousandTwentyPerformanceIncentiveAndTwoThousandFifteenEquityIncentivePlanMember" name="TwoThousandTwentyPerformanceIncentiveAndTwoThousandFifteenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_TwoThousandTwentyPerformanceIncentivePlanMember" name="TwoThousandTwentyPerformanceIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_UnvestedCommonStockUponEarlyExerciseOfCommonStockOptionsMember" name="UnvestedCommonStockUponEarlyExerciseOfCommonStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_VivariumMember" name="VivariumMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_AccountingPoliciesTable" name="AccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_IncomeTaxesTable" name="IncomeTaxesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="nktx_CashCashEquivalentsShortTermInvestmentsAndRestrictedCashPolicyTextBlock" name="CashCashEquivalentsShortTermInvestmentsAndRestrictedCashPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_PreferredStockPurchaseRightLiabilityPolicyTextBlock" name="PreferredStockPurchaseRightLiabilityPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_ReverseStockSplitPolicyPolicyTextBlock" name="ReverseStockSplitPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_ScheduleOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock" name="ScheduleOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_ScheduleOfShareBasedCompensationAdditionalInformationRelatedToStockOptions" name="ScheduleOfShareBasedCompensationAdditionalInformationRelatedToStockOptions" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_ScheduleOfSupplementalInformationRelatedToOperatingLeasesTableTextBlock" name="ScheduleOfSupplementalInformationRelatedToOperatingLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_SummaryOfCommonStockReservedForFutureIssuanceTableTextBlock" name="SummaryOfCommonStockReservedForFutureIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_TemporaryEquityPolicyTextBlock" name="TemporaryEquityPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="nktx_UnusualOrInfrequentItemsDisclosurePolicyTextBlock" name="UnusualOrInfrequentItemsDisclosurePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
