中国水利水电第三工程局有限公司工会

《中国水利水电第三工程局有限公司工会》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、ClonalDiversificationofLymphocytesReviewoflastlectureBoneMarrowThymusWheneverimmaturepre-TCellsrecognizeself-antigens,theyareprogrammedtoauto-destructintheThymusWhereasMatureTcellsproliferatewhentheycontactantigens98%pre-TcellsdieinthethymusBoneMarrowWhenimmaturepre-BCellsrecognizeself-antigensthent

2、heyauto-destructintheBoneMarrowClonesofMatureBCellsproliferatewhencontactingantigenTolerancetoselfsubstancesTreatmentsforAutoimmunediseases-WipeoutthematureBcells//Reboot–someexceptionsSjögren'sSyndromeAntigen123OnecloneofBcells(Blymphocytes)bydefinitionwillonlybindtoonetypeofantigenicdeterminante.g

3、.,eithertooutsidedeterminant#1orto#2orto#3BCellclone#2BCellclone#1MatureBCellsAntigen123FcregionFabregionBCellclone#2BCellclone#1PlasmaCellclone#1PlasmaCellclone#2Multi-clonalantibodiesAfterproliferating,manyantigenstimulatedBCellsdifferentiateintoPlasmaCellsMulticlonalStimulationActivationofspecifi

4、cclonesofBcellsPolyclonalActivation(non-specificactivationofallBcellclonesintheareabyi.e.,endotoxicLPS)Poly-CARBOHYDRATEANTIGEN-repeatingantigenicdeterminantsBCellPROTEINANTIGENNOrepeatingAntigenicdeterminantsRequiresTCellhelpIgMIgGIgAHelpcomesviasolublesubstancesproducedbystimulatedHelperTCellsBCel

5、lIgMCross-linksNoCross-linksarepossibleHelperTCellsCytotoxicTCellsCD4positiveCD8positiveTLYMPHOCYTESTCellsThTcHelperTCellshelpBCellsandCytotoxicTCellsHelperTCellclonesTCellshaveTCellReceptorsontheirsurfaceNotantibodiesAntigenEveniftheydointeract,nostimulationoftheHelperTCell----Theantigenicdetermina

6、ntsarehiddenwithintheantigen(arenotyetprocessed),andneedtobeassociatedwithaMHC2productBindinsomecasesviasurfaceantibody(sometimespassivelyabsorbed)orviacomplementdepositedontheantigenthenPhagocytizetheantigen(seethelecturehandout).FollowedbyDIGESTIONoftheantigenthatmustoccurwithoutinfectingthecell.N

7、oteAbandcomplementneutralizetheantigen.AntigenPresentingCellsDONOTHaveTCellReceptorsAntigenPresentingCellsAlltypesofAntigenPresentingCells(APC)continuallyproduceMajorHistocompatibilityComplexClassIIPr