简介：

简介：AccumulatingevidencehasdemonstratedthatregulatoryT(Treg)cellsplayanimportantroleinthemaintenanceofimmunologicself-toleranceandindown-regulatingvariousimmuneresponses.Thus,therehasrecentlybeenanincreasinginterestinstudyingthebiologyofTregcellsaswellastheirpotentialapplicationintreatingimmunediseases.ManytypesofTregcellsubsetshavebeenreportedinavarietyofdiseasemodels.Amongthesesubsets,αβ-TCR+CD3+CD4-CD8-doublenegative(DN)TregcellsaredefinedbytheircapabilityofinhibitingimmuneresponsesviadirectlykillingeffectorTcellsinanantigenspecificfashion.Furthermore,DNTregcellshavebeenshowntodevelopregulatoryactivityafterencounteringspecificantigens,partiallymediatedbytheacquisitionofMHC-peptidecomplexesfromantigenpresentingcells(APCs).ThepresentationofacquiredalloantigensonDNTcellsallowsforthespecificinteractionbetweenDNTregcellsandalloantigenreactiveeffectorTcells.OncetheDNTregandtargetcellshavecomeintocontact,killingisthenmediatedbyFas/Fas-ligandinteractions,andperhapsthroughotherunidentifiedpathways.Furthercharacterizationofthefunctions,molecularexpressionandmechanismsofactivationofDNTregcellswillhelpinthedevelopmentofnoveltherapiestoinduceantigenspecifictolerancetoselfandforeignantigens.Cellular&MolecularImmunology.2004;1(5):328-335.