15-病毒学virus巴斯德研究所

1VaccinesagainstviraldiseasesVincentDEUBELCourseonBasicVirologyandImmunology,20062VirusinfectionTypeofvirusNatureofvirusDoseofvirusRoutesofinfectionOralNasalCutaneousIntradermalParenteralSexualHostAgeRaceGeneticpredispos.ImmunestatusHealthconditionNutritionalcond.ImmunemechanismsagainstviralinfectionNatureofresponsesTypeofresponsesLevelofresponses3Natureofadaptiveimmunity:concernforvaccinesHumoralProtectiveSurfaceantigen(Nt,ADC’L,ADCC)(Receptor-Fusion)Majorcontributionto(re)infectionLong-lastingmemoryEvasiontoNt:•carbohydrates(Eproteinvaccinewithoutcarbohydrates?)•mutations•Reassortment4Natureofadaptiveimmunity:concernforvaccinesCellularCD4helperBarelyprotective(m)Majorviralantigens(MHCII)CD8CTLBarelyprotective(M)Allviralantigens(MHCI)-b2M)ContributiontoinfectedcelleliminationContributiontorestrictvirusreplication(CD8-cytokines)CooperationinB-cellresponse(CD4H)ButepitopeandMHCdependent5Natureofadaptiveimmunity:concernforvaccinesNeutralizingantibodiesagainstenvelopeproteinNonneutralizingantibodiesmayhaveanti-viralactivityIgGvsIgAanti-viralactivity.Wayofvaccination?ADEphenomenonRoleofADCCandADC’LT-cellimmunitylessefficientandHCMdependentCTLmaybedeleterious(balance)Conclusions:6Natureofadaptiveimmunity:concernforvaccines(cont.)RealadvantageofincorporationofCTLepitopesinavaccinepreparation?MHC-dependentShortdurationofimmunitySmallnumberofepitopesinavirusEscapemutantsbymutationinsidetheepitopeVaraibilityofthestrengthofimmunityamongepitopesPossibleCTL-drivenimmunopathogenesisPeptidevaccinenotgoodCTLinducerActiveonlyoninfectedcellsRoleofNonNtAbinprotectionagainstvirusinfectionImmunecomplexwithvirusinducesclearanceAbsdirectedagainstenvelopeproteinpreventvirusrelease(budding)CelllysisviaIgG-Fc-dependentmechanismConclusions(cont.):7TherapeuticofProphylacticvaccinesShortperiodforreplication:Prophylactic(polio,measles)Deleteriousforthefetus:Prophylactic(rubella)Longperiodofincubation:Therapeutic(rabies,smallpox)Chronicinfection:Prophylacticorimmunotherapy(HSV,VZV)Cancers:Prophylacticorimmunotherapy(HBV,HPV)Wayofvaccination:Injection,oral,cutaneous,passive,humantransmission8CurrentlicensedvaccinesVirusSerotypesLiveInactivatedDosesInjectionAttenuationAdenovirus2,4,7+1OralJapaneseenc.1+2PBHKMeasles1+1+RPCEMumps1+1PCEPolio1,2,3+1OMKCRotavirus1,2,3,4+3OReassortantRRVSmallpox1+1IDNaturalJennerVarizella1+1PMKCYellowfever1+1PCEHepatitisA1+2PHepatitisB1VLP3PInfluenzaA,B+1PJapaneseenc.1+3+RPPolio1,2,3+2PRabies1+xPTick-borneenc.1+2+RPAttenuation:Ts,IRES,Eprotein…9LivevirusvaccinesAdvantage:Systemicandlocalimmuneresponse.Balancedhumoralandcell-mediatedresponse.Mucosalimmunitymoreefficientwithlivevirus.Severalimmunogenicproteins.Longlastingimmunity.Lowercost.Disadvantages:Attenuationmarkersgenerallyunknown.Measles,rubella,YFwithresidualvirulence.Geneticinstabilityandreversiontovirulencepossible(polio).Immunodeficienthosts.Pregnantwomen.Immunosuppression(measles).Remainingcontaminants(allergies)Maintenanceofthecoldchain.10FutureliveattenuatedvirusvaccinesPreviouspreparation:PassageatlowtemperatureChemicalmutagenesisandselectionofmutantswithdesiredphenotype*PassageinheterologoustissuesNewpreparationofattenuatedviruses:ReversegeneticsanddirectedmutationsMissensemutationinproteinfunctions(ts,proteaseactivation,receptorrecognition,fusionactivity)Disadvantage:Reversions?Deletionstooattenuatedviruses?Insertions:genesencodingproteinsthatrestrictvirusreplication(cytokines.IL)reducedimmunogenicity,stability?Mutationsinthenoncodingregions(tissue-orhost-specificity,sensitivitytoIFN,levelofreplication):obtainedbypointmutation,deletions,sequencesexchanges*Ts,smallplaque,mousevirulence…11Futureliveattenuatedvirusvaccines(cont.)Newpreparationofattenuatedviruses(Cont.):JennerianapproachGenesexchangesofanimalandhumanviruses(rota,influenza)GeneincompatibilityExchangegeneofoneproteininaproteincomplex(polymerasecomplexhumanPB1&PAandavianPB2;HSV1&HSV2)ChimericvirusesProtectiveantigensinabackboneofattenuatedvirus(Rota,YF,Measles,Vaccinia):substitutionoraddition.12InactivatedvirusvaccinesSupports:EmbryonatedVeroHumanMouseChickeneggsDiploidbrainfibroblastsfibroblastsVirusInfluenzaPolioHep.AJEVTBERabiesInactivationDetergentFormalinFormalinFormalinFormalinPurificationSucroseChromatographygradientNbdosesoneone32severalRoleofinactivationandofpurificationonimmunogenicity?PotentiationroleofTcellresponseintheabsenceofNtAb?13RecombinantantigensExpressionsystems:BacteriaYeastMammaliancellsInsectcellsAviancellsPlantsDNA(Genegun.BandTcellresponse)Typeofantigens:Particulate(VLP)Soluble(monomericordimeric)FusionproteinChimericVLPs(emptyshell):veryefficientininductionofNtAbs(TBE,JEV,HPV,parvovirusB19):Conformationalepitopesimilartothevirus,efficientproductionforvirusesthatdonotgrowincellculture,nodenaturinginactivation,betterimmuneresponsethantomonomericprotein).14RecombinantvaccinesViralvectorsofrecombinantproteins:Vaccinia(AnkaraMVA,avianpoxvirus)AdenovirusRhabdovirus(VSV)MeaslesYFReplicationdefectiveviruses(H