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      </link:roleType>
      <link:roleType roleURI="http://www.cerus.com/taxonomy/role/DisclosureSegmentCustomerAndGeographicInformationAdditionalInformation" id="DisclosureSegmentCustomerAndGeographicInformationAdditionalInformation">
        <link:definition>152 - Disclosure - Segment, Customer and Geographic Information - Additional Information (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.cerus.com/taxonomy/role/DisclosureSignificantCustomersThatAccountedForMoreThanTenPercentageOfTotalProductRevenue" id="DisclosureSignificantCustomersThatAccountedForMoreThanTenPercentageOfTotalProductRevenue">
        <link:definition>153 - Disclosure - Significant Customers that Accounted for More than Ten Percentage of Total Product Revenue (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:href="cers-20130630_cal.xml" xlink:title="Calculation Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:href="cers-20130630_def.xml" xlink:title="Definition Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:href="cers-20130630_lab.xml" xlink:title="Label Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:href="cers-20130630_pre.xml" xlink:title="Presentation Links, all"/>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <import namespace="http://fasb.org/us-types/2013-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2013/elts/us-types-2013-01-31.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd"/>
  <import namespace="http://fasb.org/us-gaap/2013-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/country/2013-01-31" schemaLocation="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/currency/2012-01-31" schemaLocation="http://xbrl.sec.gov/currency/2012/currency-2012-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/dei/2013-01-31" schemaLocation="http://xbrl.sec.gov/dei/2013/dei-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/exch/2013-01-31" schemaLocation="http://xbrl.sec.gov/exch/2013/exch-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd"/>
  <element name="AccruedInventory" id="cers_AccruedInventory" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AmountUnderRevolvingLineOfCreditAvailableToCompany" id="cers_AmountUnderRevolvingLineOfCreditAvailableToCompany" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AumLtdMember" id="cers_AumLtdMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AvailableForSaleSecuritiesDisclosureTextBlock" id="cers_AvailableForSaleSecuritiesDisclosureTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="BravoPacificLimitedMember" id="cers_BravoPacificLimitedMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CantorMember" id="cers_CantorMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CapitalLoanMember" id="cers_CapitalLoanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CashEquivalentsMaturityPeriod" id="cers_CashEquivalentsMaturityPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ClassOfWarrantOrRightCommonStockExchangeRatio" id="cers_ClassOfWarrantOrRightCommonStockExchangeRatio" type="xbrli:decimalItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ClassOfWarrantOrRightNumberOfSharesOfCommonStock" id="cers_ClassOfWarrantOrRightNumberOfSharesOfCommonStock" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CommitmentsAndContingenciesDisclosureLineItems" id="cers_CommitmentsAndContingenciesDisclosureLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CommitmentsAndContingenciesDisclosureTable" id="cers_CommitmentsAndContingenciesDisclosureTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="CommonStockSharesAvailableForSaleValue" id="cers_CommonStockSharesAvailableForSaleValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ComplianceWithCovenantsMember" id="cers_ComplianceWithCovenantsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ConcentrationRiskPercentageOfRevenuesBySingleCustomer" id="cers_ConcentrationRiskPercentageOfRevenuesBySingleCustomer" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ConcordLeaseMember" id="cers_ConcordLeaseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ConversionOfPreferredStockToCommonStockDate" id="cers_ConversionOfPreferredStockToCommonStockDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CumulativeOutstandingTradeReceivablesMajorCustomersPercentage" id="cers_CumulativeOutstandingTradeReceivablesMajorCustomersPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CumulativeOutstandingTradeReceivablesNumberOfMajorCustomers" id="cers_CumulativeOutstandingTradeReceivablesNumberOfMajorCustomers" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CustomersThatAccountedForMoreThanTenPercentageOfCompanysProductRevenueTableTextBlock" id="cers_CustomersThatAccountedForMoreThanTenPercentageOfCompanysProductRevenueTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentCarryingCurrent" id="cers_DebtInstrumentCarryingCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentCarryingNonCurrent" id="cers_DebtInstrumentCarryingNonCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentUnamortizedCurrent" id="cers_DebtInstrumentUnamortizedCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentUnamortizedNoncurrent" id="cers_DebtInstrumentUnamortizedNoncurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DelrusIncMember" id="cers_DelrusIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DenominatorAbstract" id="cers_DenominatorAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DerecognitionOfTaxPositions" id="cers_DerecognitionOfTaxPositions" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DesignatedPreferredStockForFutureIssuance" id="cers_DesignatedPreferredStockForFutureIssuance" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DocumentDocumentAndEntityInformationAbstract" id="cers_DocumentDocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EarlyTerminationOfNonCancelableOperatingLeasesMinimumPeriod" id="cers_EarlyTerminationOfNonCancelableOperatingLeasesMinimumPeriod" type="xbrli:gYearMonthItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EarningsPerShareDisclosureLineItems" id="cers_EarningsPerShareDisclosureLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EarningsPerShareDisclosureTable" id="cers_EarningsPerShareDisclosureTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="EligibleToReceiveRoyaltyFee" id="cers_EligibleToReceiveRoyaltyFee" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeStockPurchasePlanMember" id="cers_EmployeeStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EtablissementFrancaisDuSangMember" id="cers_EtablissementFrancaisDuSangMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ExercisablePeriod" id="cers_ExercisablePeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ExpirationOfNonCancelableOperatingLeasesMaximumYear" id="cers_ExpirationOfNonCancelableOperatingLeasesMaximumYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueOfWarrantsTableTextBlock" id="cers_FairValueOfWarrantsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FinalPaymentFeePercentage" id="cers_FinalPaymentFeePercentage" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizationExpenseYearEight" id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearEight" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizationExpenseYearSeven" id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearSeven" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizationExpenseYearSix" id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearSix" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GoodwillAndIntangibleAssetsDisclosureTable" id="cers_GoodwillAndIntangibleAssetsDisclosureTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="GrowthCapitalLoanMember" id="cers_GrowthCapitalLoanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseInSharesOfCommonStockAuthorizedForIssuance" id="cers_IncreaseInSharesOfCommonStockAuthorizedForIssuance" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InventoryLifeFinishedGoodsPeriod" id="cers_InventoryLifeFinishedGoodsPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LeaseholdImprovementReflectedInAccruedLiabilities" id="cers_LeaseholdImprovementReflectedInAccruedLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LeaseholdImprovementReflectedInOtherNonCurrentLiabilities" id="cers_LeaseholdImprovementReflectedInOtherNonCurrentLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LicenseAgreementsTextBlock" id="cers_LicenseAgreementsTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LicensesAgreementsLineItems" id="cers_LicensesAgreementsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LicensesAgreementsTable" id="cers_LicensesAgreementsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="LineOfCreditFacilityAnnualCommitmentFeeAmount" id="cers_LineOfCreditFacilityAnnualCommitmentFeeAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityInterestPaymentPeriod" id="cers_LineOfCreditFacilityInterestPaymentPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityPrincipalAndInterestRepaymentAdditionalPeriod" id="cers_LineOfCreditFacilityPrincipalAndInterestRepaymentAdditionalPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityWithdrawals" id="cers_LineOfCreditFacilityWithdrawals" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ManufacturingAndSupplyAgreementsMember" id="cers_ManufacturingAndSupplyAgreementsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumAmountAvailableUnderOffering" id="cers_MaximumAmountAvailableUnderOffering" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumNumberOfSharesOfCommonStockAuthorizedForIssuance" id="cers_MaximumNumberOfSharesOfCommonStockAuthorizedForIssuance" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinimumCashBalance" id="cers_MinimumCashBalance" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinimumPercentageOfCommonStockAcquiredByStockholders" id="cers_MinimumPercentageOfCommonStockAcquiredByStockholders" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinimumRevenuesLevelsPercentage" id="cers_MinimumRevenuesLevelsPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinimumTermOfNonCancelableOperatingLeases" id="cers_MinimumTermOfNonCancelableOperatingLeases" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MlvMember" id="cers_MlvMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MovacoSaMember" id="cers_MovacoSaMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfSharesAvailableForFutureIssuance" id="cers_NumberOfSharesAvailableForFutureIssuance" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfSharesOfCommonStockInEachUnit" id="cers_NumberOfSharesOfCommonStockInEachUnit" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumeratorAbstract" id="cers_NumeratorAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLeaseNumberOfAdditionalRenewalOption" id="cers_OperatingLeaseNumberOfAdditionalRenewalOption" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLeasesStartDate" id="cers_OperatingLeasesStartDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OptionsAndOtherStockBasedAwards" id="cers_OptionsAndOtherStockBasedAwards" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OutstandingLiabilityRelatedToLeaseholdImprovementsCurrentAndNonCurrent" id="cers_OutstandingLiabilityRelatedToLeaseholdImprovementsCurrentAndNonCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OverallotmentOptionMember" id="cers_OverallotmentOptionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OwnershipPercentageUnderCostMethodInvestments" id="cers_OwnershipPercentageUnderCostMethodInvestments" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentForManufacturingOfEntityProducts" id="cers_PaymentForManufacturingOfEntityProducts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentForRoyalty" id="cers_PaymentForRoyalty" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfInvestmentsMadeInSubsidiary" id="cers_PercentageOfInvestmentsMadeInSubsidiary" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfProceedsPayableAsCompensationToUnderwriter" id="cers_PercentageOfProceedsPayableAsCompensationToUnderwriter" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceBasedStockOptionsAwards" id="cers_PerformanceBasedStockOptionsAwards" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceBasedStockOptionsOutstanding" id="cers_PerformanceBasedStockOptionsOutstanding" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PreferredStockConversionBasisToCommonShares" id="cers_PreferredStockConversionBasisToCommonShares" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromIssuanceOfCommonStockGross" id="cers_ProceedsFromIssuanceOfCommonStockGross" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromLandlordFinancingLeaseholdImprovement" id="cers_ProceedsFromLandlordFinancingLeaseholdImprovement" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProductWarrantyMember" id="cers_ProductWarrantyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RoyaltyRateAppliedTowardsSaleOfProducts" id="cers_RoyaltyRateAppliedTowardsSaleOfProducts" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SafetyProductWarrantyPeriod" id="cers_SafetyProductWarrantyPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SalesAgreementMember" id="cers_SalesAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccruedLiabilitiesLineItems" id="cers_ScheduleOfAccruedLiabilitiesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccruedLiabilitiesTable" id="cers_ScheduleOfAccruedLiabilitiesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SettlementsOfWarrantyClaims" id="cers_SettlementsOfWarrantyClaims" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShortTermInvestmentsMaturityPeriod" id="cers_ShortTermInvestmentsMaturityPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockholderRightsPlanMember" id="cers_StockholderRightsPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockholdersEquityNoteLineItems" id="cers_StockholdersEquityNoteLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockholdersEquityNoteTable" id="cers_StockholdersEquityNoteTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SummaryOfSignificantAccountingPoliciesLineItems" id="cers_SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesTable" id="cers_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="TwoThousandEightEquityIncentivePlanMember" id="cers_TwoThousandEightEquityIncentivePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandNineUnitOfferingMember" id="cers_TwoThousandNineUnitOfferingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandNineWarrantsMember" id="cers_TwoThousandNineWarrantsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTenUnitOfferingMember" id="cers_TwoThousandTenUnitOfferingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTenWarrantsMember" id="cers_TwoThousandTenWarrantsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnderwritingDiscount" id="cers_UnderwritingDiscount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitIssuedDuringPeriodPricePerUnitNewIssues" id="cers_UnitIssuedDuringPeriodPricePerUnitNewIssues" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitsIssuedDuringPeriodUnitsNewIssues" id="cers_UnitsIssuedDuringPeriodUnitsNewIssues" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantLiabilityMember" id="cers_WarrantLiabilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantLiabilityPolicyTextBlock" id="cers_WarrantLiabilityPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantLiabilityRevaluationGainLoss" id="cers_WarrantLiabilityRevaluationGainLoss" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsExercisableDate" id="cers_WarrantsExercisableDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsExercised" id="cers_WarrantsExercised" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantyAxis" id="cers_WarrantyAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:dimensionItem"/>
  <element name="WarrantyDomain" id="cers_WarrantyDomain" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WorkInProcessInventoryLifePeriod" id="cers_WorkInProcessInventoryLifePeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ZeroPointOneOfProductSalesForPlateletSystemMember" id="cers_ZeroPointOneOfProductSalesForPlateletSystemMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ZeroPointZeroFiveOfProductSalesForRedBloodCellSystemMember" id="cers_ZeroPointZeroFiveOfProductSalesForRedBloodCellSystemMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ZeroPointZeroSixFiveOnSaleOfIlluminatorsMember" id="cers_ZeroPointZeroSixFiveOnSaleOfIlluminatorsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ZeroPointZeroThreeOfProductSalesForPlasmaSystemMember" id="cers_ZeroPointZeroThreeOfProductSalesForPlasmaSystemMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
