供体凋亡细胞输注对胰岛移植糖尿病大鼠CD4^＋CD25^＋T细胞的影响

目的探讨供体凋亡细胞输注对诱导胰岛移植免疫耐受大鼠CD4^＋CD25^＋T细胞的影响。方法糖尿病SD大鼠23只，随机分为4组，分别输注Hanks液（Hanks组）、供体正常脾细胞（正常细胞组）、供体坏死脾细胞（坏死细胞组）及供体凋亡脾细胞（凋亡细胞组）。输注后第7天行同种异体胰岛移植，测血糖，观测胰岛移植物存活时间，流式细胞仪检测受体大鼠CD4^＋CD25^＋T细胞的比例变化。结果预输注供体凋亡脾细胞能显著延长同种异体胰岛移植物存活时间（中位生存时间达31天），预输注凋亡细胞组CD4^＋CD25^＋T细胞比例明显高于其他各组（P均〈0．05）。结论供体凋亡细胞输注能够诱导同种异体大鼠胰岛移植免疫耐受，CD4^＋CD25^＋T淋巴细胞可能在其中发挥重要作用。

The effect of transfusion of donor apoptotic cells on CD4+ CD25+ T lymphocytes in diabetic rat undergoing islets transplantation

Objective To investigate the influence of transfusion of donor apoptotic cells on the the ratio of CD4^＋ CD25^＋ to CD4^＋ T lymphocytes in the rat immune tolerance to allogenic islets transplantation. Methods Recipient SD rats were rendered diabetic by a single intraperitoneal injection of streptozotoein （STZ）. Apoptotic splenocytes of donor Wistar rat were induced by X-irradiation from electron linear accelerator. Then, the donor apoptotic splenocytes were injected into the recipient SD rats. Seven days later, diabetic SD rats received islets transplantation under their renal capsule. The blood glucose and allograft survival time were detected to reflect the function of the islets grafts. The ratio of CD4^＋T to CD4^＋CD25^＋T lymphocytes was detected by flow cytometry. Results The pre-infused donor apoptotic splenocytes significantly prolonged allograft survival time（MST 31d）,and increased the ratio of CD4^＋CD25^＋ to CD4^＋ T lymphocytes both in serum and spleen tissue in apoptotie cell infusion group versus infusions of normal cell, necrotic cell and Hanks solution at 7 days after the infusion （all P〈0.05）. Conclusions Transfusion of donor apoptotic splenocytes can induce rat immunological tolerance to allogenie islets transplantation, and CD4^＋CD25^＋T lymphocytes have an important role in inducing the tolerance.