供体凋亡淋巴细胞预输注对猪肝移植受体CD4+T、CD8+T、CD4+CD25+调节性T细胞的影响

背景：凋亡细胞能够主动调节机体的免疫功能，并能通过调节机体细胞免疫和体液免疫的途径诱导免疫耐受，但这些结果只在大鼠肝脏移植模型中证实。 目的：探讨通过⁶⁰Co γ射线体外处理后的供体淋巴细胞预输注诱导猪肝移植特异性免疫耐受的作用中，对淋巴细胞亚群的影响。 方法：建立非转流小型猪原位肝移植模型。将受体猪随机摸球法均分为2组：空白对照组，受体猪无特殊处理，行肝移植；淋巴细胞组：受体猪在肝移植前7 d经耳静脉注射⁶⁰Co γ射线处理过的5×10⁸个供体淋巴细胞。观察两组受体猪移植后的存活时间，移植后T淋巴细胞亚型CD4⁺T、CD8⁺T、CD4⁺CD25⁺Tr变化及病理。 结果与结论：移植后3 d，两组病理活检均呈急性中、重度排斥反应；移植后6 d，两组均呈急性重度排斥反应。移植后1，3，6 d CD4⁺T、CD8⁺T、CD4⁺CD25⁺Tr升降趋势，两组间差异无显著意义(P > 0.05)。提示，⁶⁰Co γ射线体外处理过的淋巴细胞预输注未能够诱导猪同种异体肝移植特异性免疫耐受，未能引起T淋巴细胞亚群变化有关。

Pre-infusion of donor apoptotic lymphocytes effects on receptor CD4+T,CD8+T,CD4+CD25+ T regulatory cells during porcine liver transplantation

BACKGROUND:Apoptotic cells can actively regulate the body’s immune function, and induce immune tolerance through regulation of cellular and humoral immune, which has been only confirmed in rat liver transplantation models. OBJECTIVE:To investigate the influence of CD4⁺T, CD8⁺T, CD4⁺CD25⁺ T regulatory cells of preoperative transfusion of lymphocyte from in vitro ⁶⁰Coγ-treated donor porcine on allograft survival of orthotopic liver transplantation (OLT). METHODS: OLT models were performed without veno-venous bypass (VVB) in Chinese inbred miniature porcine. The recipient porcine were administrated intravenously with donor apoptotic lymphocyte (5×10⁸) 7 days before liver transplantation, or not treated. Changes of CD4⁺T, CD8⁺T, CD4⁺CD25⁺ T regulatory cells and liver pathological changes were observed after the transplantation. Apoptotic percentage of lymphocytes from in vitro 60Coγ-treated was measured by flow cytometry using AnnexinⅤ/PI double staining method. RESULTS AND CONCLUSION:Liver grafts biopsy of two group showed the same change after operation, there were mild or serious acute rejections on the 3rd day after operation, and serious acute rejection on the 6th day. The increasing changes of CD4⁺T, CD8⁺T and CD4⁺CD25⁺T regulatory cells were just like the change of lymphocytes. But the contrast of two group was of non-significance (P >0.05). These indicate that immunological tolerance cannot be induced by transfusion of preoperative donor 60Coγ-treated lymphocytes in porcine liver allograft, preoperative transfusion of lymphocytes cannot influence the expression of CD4⁺T, CD8⁺T, CD4⁺CD25⁺ T regulatory cells in tolerance receptor of porcine liver transplantation.