CTLA-4Ig联合髓腔内骨髓移植诱导小鼠同种异体皮肤移植耐受的研究

Induction of tolerance skin allograft by combined application of CTLA4-Ig and intra-bone-marrow injection of bone-marrow cells

目的探讨细胞毒性T淋巴细胞相关抗原4免疫球蛋白(Cytotoxic T Lymphocyte Antigen4-immunoglobulin,CTLA4-Ig)与髓腔内骨髓移植(IBM-BMT)联合应用对诱导供体小鼠皮肤移植免疫耐受的促进bd作用。方法受鼠为C57BL/6(H-2,B6)雌性小鼠,于第0天输注雄性BALB/c(2)小鼠来源的骨髓细胞(BMC),同时腹腔注射CTLA4-Ig;第6天进行皮肤移植,并于移植术后第2天再进行一次腹腔注射CTLA4-Ig,观察皮肤移植物存活时间。通过皮肤移植物的组织学分析,以及混合淋巴细胞反应(MLR)检测耐受状态,并通过骨髓染色体分析了解BMT的植入程度。结果联合治疗组B6小鼠的皮肤移植物平均存活时间(MST)显著长于其它各组(P<0.05);MLR结果证明,联合组B6小鼠获得供体特异性耐受,在耐受小鼠骨髓中可检测到一定比例的Y染色体存在。结论 CTLA4-Ig与髓腔内骨髓移植可保证异基因的骨髓细胞形成嵌合体,显著延长了移植物存活时间,诱导免疫耐受。

Objective To explore the facilitation about the immune tolerance to murine skin allograft induced by combined application of cytotoxic T lymphocyte antigen 4-immunoglobulin（CTLA4-Ig） and intra-bone-marrow injection of bone-marrow. Methods C57BL/6（H-2b,B6） mice were injected with bone marrow cells originated from BALB/c（2d）mice at day 0, meanwhile an intraperitoneal injection of CTLA4-Ig was given. Skin grafting was performed at day 6, CTLA4-Ig was given again two days after the transplantation, then the survival time of donor skins was observed. histopathology of the donor skin allograft and mixed lymph cell reaction（MLR） were performed to examine the status of immune-tolerance and chromosome analysis was used to investigate engrafting of allergenic bone-marrow cells. Results It was found that the mean survival time（MST） of BALB/c skin allograft in B6 recipients treated by CTLA4-Ig combined with bone marrow cells infusion was significant longer than that of other groups, and MLR assay demonstrated the donor-specific tolerance existing in the recipient mice with percentage of donor-specific cells in bone marrow of tolerant B6 mice at day 30. Conclusion Combined application of CTLA4-Ig and intra-bone-marrow injection of bone-marrow could induce immunotolerance to routine skin allograft.