简介：<正>Fasligand(FasL)wasfirstdescribedfunctionallyasaninduciblecellsurfacemoleculeusedbycytotoxicTcellstoinduceapoptoticcelldeathintumorcellsandactivatedlymphocytes.WiththeidentificationofFasastheIprgeneproduct,FasLbecamerecognizedasamoleculeinvolvedindown-regulationoftheimmunesystem.WhileFasLcanbeusedtoefficientlykillFas-expressingtumorcellsaswellasactivatedTandBlymphocytesinvitro,attemptstouseFasLtherapeuticallytotreatcancerortopreventtransplant

简介：ApoptosisproducedinBcellsthroughFas(APO-1,CD95)triggeringisregulatedbysignalsderivedfromothersurfacereceptors:CD40engagementproducesupregulationofFasexpressionandmarkedsusceptibilitytoFas-inducedcelldeath,whereasantigenreceptorengagement,orIL-4Rengagement,inhibitsFaskillingandinsodoinginducesastateofFas-resistance,eveninotherwisesensitive,CD40-stimulatedtargets.SurfaceimmunoglobulinandIL-4RutilizeatleastpartiallydistinctpathwaystoproduceFas-resistancethatdifferentiallydependonPKCandSTAT6,respectively.Further,surfaceimmunoglobulinsignalingforinducibleFas-resistancebypassesBtk,requiresNF-κB,andentailsnewmacromolecularsynthesis.TerminaleffectorsofBcellFas-resistanceincludetheknownanti-apoptoticgeneproducts,Bcl-XLandFLIP,andanovelanti-apoptoticgenethatencodesFAIM(FasApoptosisInhibitoryMolecule).faimwasidentifiedbydifferentialdisplayandexistsintwoalternativelysplicedforms;faim-Sisbroadlyexpressed,butfaim-Lexpressionistissue-specific.TheFAIMsequenceishighlyevolutionarilyconserved,suggestinganimportantroleforthismoleculethroughoutphylogeny.InducibleresistancetoFaskillingishypothesizedtoprotectforeignantigen-specificBcellsduringpotentiallyhazardousinteractionswithFasL-bearingTcells,whereasautoreactiveBcellsfailtobecomeFas-resistantandaredeletedviaFas-dependentcytotoxicity.InadvertentoraberrantacquisitionofFas-resistancemaypermitautoreactiveBcellstoescapeFasdeletion,andmalignantlymphocytestoimpedeanti-tumorimmunity.

简介：<正>ThesusceptibilityofprimaryBcellstoFas(APO-1,CD95)-mediatedapoptosisisregulatedbysignalsderivedfromadditionalsurfacereceptors.CD40engagementproducesupregulationofFasexpressionandinducesmarkedsensitivitytoFas-inducedcelldeath,whereasBcellantigenreceptor(BCR)engagementinhibitsFaskillingandtherebyproducesFas-resistance,eveninotherwisesusceptible,CD40-stimulatedtargets.BCRsignalingforinducibleFas-resistancedevelopsoveraperiodof12hoursanddependson

简介：Fas/CD95表面受体调停各种各样的房间的快速的死亡打字，包括有为触发autoimmunity的潜力的autoreactiveT房间。这里，我们表明那的船边交货的现在的新奇方面定义一种“社会”的尺寸到导致受体的apoptosis。船边交货刺激很快导致在附近的T房间之间的广泛的膜nanotube形成。这极其依赖于RhoGTPases然而并非在caspase激活上。包括活跃caspases的膜和cytosolic元素的双向转移能被观察经由这些nanotubes发生。Nanotube形成和死亡信号的细胞间的交换在从有在船边交货受体的自体免疫的lymphoproliferative症候群harbouring变化的病人的T淋巴细胞是有缺点的。我们断定调停nanotube的交换组成扩充在附近的T房间之间发信号的死亡的繁殖的细胞间的通讯的一种新奇形式。

简介：Apoptosisplaysanimportantroleinembryonicdevelopment,tissueremodeling,immuneregulationandtumorregression.Twogroupsofmolecules(Bcl-2familyand“Deathfactor”family)areinvolvedinregulatingapoptosis.InordertoknowabouttheeffectofBcl-2onapoptosisinducedbyFas,atypicalmemberof“Deathfactor”family,thetransfectionexperimentswithexpressionvectorspcDNA3-flandpcDNA3-bcl-2wereperformedinBEL-7404cells,ahumanhepatocellularcarcinomacelllinewhichexpressesendogenousFas,butnotFasLandBcl-2.ThedatashowedthattheexpressionofFasLinpcDNA3-fltransfectedhepatomacellsobviouslyinducedtheapoptosisofthecells.However,theoverexpressionofBcl-2inpcDNA3-bcl-2transfected7404/b-16cellscounteractedpcDNA3-fltransienttransfectionmediatedapoptosis.FurtherstudybycotransfectionexperimentsindicatedthatBidbutnotBax(bothwerepro-apoptoticproteinsofBcl-2family)blockedtheinhibitoryeffectofBcl-2onFas-mediatedapoptosis.TheseresultssuggestedthatFas-mediatedapoptosisinhumanhepatomacellsispossiblyregulatedbyBcl-2familyproteinsviamitochondriapathway.