摘要
IncreasedexpressionofFasbyhematopoieticprogenitorsinaplasticanemia(AA)suggeststhatFas/Fasligand(FasL)systemplaysakeyroleintheformationofseverepancytopenia.Tofurtherconfirmtheabovehypothesis,Tcellsfrom8patientswithAAweresystematicallystudiedfortheirFasL'sdistributionpattern,releasingmannerandproapoptoticactivity,comparedwithnormalrestingTcellsandartificiallyactivatedTcellblasts.TheresultsdemonstratedthatAATcellsabnormallyexpressedlowlevelsofmembrane-boundFasLandcontainedhighlevelsofintracellularFasLwhichcouldbetriggeredtoreleasebyhigh-dosephytohemagglutinin(PHA)pulse-stimulation.ThesupernatantsfromthePHA-stimulatedAATcellshadapparentcytotoxicityagainstFasL-sensitiveJurkatcells,whichcouldbesignificantlyinhibitedbymonoclonalantibodyagainstFasLinadose-dependentmanner,ornearlycompletelyabrogatedbyultracentrifugation.TheabovephenomenaalsoappearedonartificiallyactivatedTcellblasts,butthiswasnotthecaseonnormalrestingTcells.TheseresultsindicatethatAATcellisatypeof'preactivated'Tlymphocyte,characterizedbyoverexpressionofFasL,especiallyintracellularFasLwhichcanbestimulatedtoreleaseinbioavtiveexosomesboundform.Takentogether,ourdataprovidefurtheranddirectevidenceforthehypothesisthatTcellsmightmediatethedestructionofhematopieticprogenitorinAAthroughFas/FasLsystem.
出版日期
2004年02月12日(中国期刊网平台首次上网日期,不代表论文的发表时间)