NKG2D mAb对自发性NOD小鼠同种胰岛移植的作用研究

The Effects of NKG2D mAb on the Survival of Allogeneic Transplanted Islets in Spontaneous Diabetic Nonobese Diabetic Mice

目的探讨NKG2D mAb能否单独作为共刺激信号阻断剂延长自发性非肥胖型糖尿病(NOD)小鼠移植移岛的有功能存活期;NKG2D mAb和CD154 mAb是否有协同作用。方法将分离、纯化的BABL/c小鼠胰岛植入自发糖尿病的NOD小鼠左肾包膜下,移植成功的小鼠分成4组:对照组,NKG2D mAb治疗组,CD154 mAb治疗组和联合治疗组(NKG2D mAb+CD154 mAb)。通过小鼠尾静脉血监测血糖,记录胰岛移植物有功能存活期;胰岛移植物所在肾脏行HE染色和CD3、CD4、CD8免疫组织化学染色。结果 NKG2D mAb治疗组移植物有功能存活期无延长(5~11 d,对照组6~11 d,两者差异无统计学意义),CD154 mAb治疗能明显延长移植物有功能存活期〔20~64 d,中位期41 d,和NKG2D mAb治疗组及对照组比较差异均有统计学意义(P<0.05)〕,联合治疗组较CD154 mAb治疗能延长移植物有功能存活期(23~84 d,中位期51 d,但差异无统计学意义)。各组发生排斥时胰岛移植所在肾脏均见淋巴细胞浸润,CD3、CD4、CD8染色结果无明显差异。结论 CD154 mAb能明显延长NOD小鼠胰岛移植物有功能生存期;单独使用NKG2D mAb治疗,不能延长胰岛移植物有功能生存期;联合治疗有效,但仍不能诱导移植物长期存活。

Objective To investigate the effects of NKG2D mAb on the survival of allogeneic transplanted islets nonobese diabetic(NOD) mice,and to find if CD154 mAb has synergistic effects.Methods Spontaneous diabetic NOD mice transplanted with allogeneic islets of BALB/c mice were divided into 4 groups.Group A was control group,Group B were treated with anti-NKG2D monoclonal antibody(mAb),Group C were treated with CD154 mAb(MR1),Group D were treated with NKG2D mAb and MR1.Glucose levels were monitored at regular intervals through caudal vein,and islet function was evaluated by glycemia.Histological study was performed at graft rejection or at day 120.Spleen cell suspension was prepared for mixed lymphocyte cultivation.The kidneys hosting the islet graft were prepared with HE staining and immuno-histochemistry staining of CD3,CD4 and CD8 was performed. Results MR1 therapy alone significantly prolonged the survival of islet grafts when compared to NKG2D mAb group and the control group: median graft survival was 41 days versus 8 days(P0.05).Conclusion NKG2D mAb alone did not result in the prolongation of islet graft survival,whereas CD154 mAb increased graft survival.When both antibodies were administered,a synergistic effect was obtained,but did not provide permanent protection from diabetes recurrence.