CD4^＋CD25^＋调节性T细胞对同种胰岛移植免疫耐受的影响

CD4^＋CD25^＋ regulatory T cells induced immuno-tolerance of pancreatic islet allografts

目的观察体外分离的CD4^＋CD25^＋调节性T细胞对同种胰岛移植免疫耐受的影响。方法免疫磁珠法分离CD4^＋CD25^＋调节性T细胞，体外试验观察其对CD4^＋CD25^- T细胞增殖的影响。将数量达1×10^6的CD4^＋CD25^＋调节性T细胞回输胰岛移植受体，对比其对移植物存活的影响。结果分离的CD4^＋CD25^＋调节性T细胞体外试验可明显抑制CD4^＋CD25^-T细胞的增殖。单纯胰岛移植组移植物物存活期为（5．57±0．79）d，回输受体CD4^＋CD25^＋调节性T细胞数量1×10^6、2×10^6时，胰岛移植物存活时间分别为（15．29±2．29）d和（25．43±2．30）d（P〈0．01）。CD4^＋CD25^＋调节性T细胞回输胰岛移植受体可显著延长移植物存活期，诱导免疫耐受的作用为剂量依赖性。结论CD4^＋CD25^＋调节性T细胞体外、体内试验可抑制效应性T细胞功能，诱导胰岛移植免疫耐受。

Objective To investigate the immune tolerance of pancreatic islet allografts induced by isolated CD4^＋CD25^＋ regulatory T cells. Methods Magnetic cell sorting system was used to isolate CD4^＋CD25^＋ regulatory T cells, and cell proliferation assay to analyze the suppressive effect of CD4^＋CD25^＋ regulatory T ceils on the proliferation of CD4^＋CD25^＋T effector in vitro. Isolated CD4^＋CD25^＋ regulatory T cells （ 1 × 10^6 and 2 × 10^6 ） were injected intravenously into the recipient before islet transplantation, and the survival time was compared between the group of single islet transplantation and that of CD4^＋CD25^＋ regulatory T cells treatment. Results Isolated CD4^＋CD25^＋ regulatory T cells suppressed the proliferation of CD4^＋CD25^＋T cells in vitro. The survival time of the group of CD4^＋CD25^＋ regulatory T cells treatment was 15.29 ± 2.29 days and 25.43 ±2.30 days ,significantly longer than that of single islet transplantation （both P 〈 0.01 ）. Conclusion CD4^＋CD25^＋ regulatory T cells can suppress the CD4^＋CD25^-T effector ceils, and induce immune tolerance of pancreatic islet allografts.