异种骨移植时T淋巴细胞总数及亚群的变化

EffectofbonexenografttransplantationontotalTlymphocyteanditssubsetcountsinmousebloodandspleen

以新鲜小牛松质骨（ＦＸ）、脱抗原处理的牛松质骨载体（ＢＣ）及不同复合比例的重组合异种骨（ＲＢＸ）植入Ｂａｌｂ／ｃ小鼠股部肌袋内，正常小鼠模拟手术做为对照组。术后７、１４及２８天，取材做组织学检查，同时以间接免疫荧光法测定外周血及脾脏淋巴细胞中Ｔｈｙ１、Ｌ３Ｔ４、Ｌｙｔ２及Ｔａｃ阳性细胞百分数。结果示：脱抗原载体植入组与正常对照组无明显差异。ＦＸ组阳性淋巴细胞百分数均明显升高，以Ｔａｃ升高显著；组织学示局部免疫排斥而无骨诱导生成。ＲＢＸ植入组Ｔａｃ无增高，组织学见活跃的异位诱导成骨而无免疫排斥反应，但Ｔｈｙ１及Ｌｙｔ２细胞荧光染色阳性率增高，以Ｌｙｔ２增高明显，Ｔｈ／Ｔｓ比值下降或倒置，为ＲＢＸ中所含ＢＭＰ所致。这一现象可能与机体对异种ＢＭＰ及ＲＢＸ不引起明显免疫排斥有关。Ｔａｃ细胞阳性表达率对评价异种骨移植时免疫排斥反应有一定的意义。

Freshcalfcancelousbonexenograft(FX),antigenfreecancelousbonecarrier(BC)andreconstitutedbonexenograft(RBX)wereinplantedinthethighmusclepouchesofBalb/cmice.Histo-logicalexaminationsweredoneat7,14and28dayspostoperation,andindirectimmunofluorescencewasusedtodeterminethepositivecountsofThy1,L3T4,Lyt2,andTacTlymphocyteofthebloodandspleenatthesametime,withthenormalmouselymphocytesascontrol.Therewasnosignificantdifer-encebetweentheBCimplantedgroupandthenormal(control)group,whiletheFXgrouphadasignifi-cantincreaseratesofThy1、L3T4andLyt2,especialyofTaclymphocytes.TheRBXimplantedgrouphadnoincreaseofTacbutincreaseofThy1andLyt2.Th-Tsratiodecreased,anditwasprobablycausedbybovinebonemorphogeneticprotein(bBMP)intheRBX.Histologicaly,intenseimmunerejectionwasnotedinFXimplantedgroupbutnotintheothertwogroups.HeterotopicossificationwasnotedintheRBXimplantedgroup.FXincreasedintenseimmunologicrejectioninthehost,batRBXdidnot,thatmightbeduetothedecreaseofTh/TscausedbybBMP.Taclymphocytecountmayindicatetheim-munologicrejectionofbonexenografttransplantation.