Ad-CTLA-4Ig基因导入对胰十二指肠移植大鼠免疫耐受的实验研究

目的 研究基因转导法导入细胞毒性T淋巴细胞相关抗原-4融合蛋白基因(CTLA-4Ig)对诱导大鼠胰腺移植免疫耐受的作用.方法 采用链脲霉素60 mg/kg尾静脉一次性注射法诱导建立Wistar大鼠Ⅰ型糖尿病模型.以SD大鼠为供体,糖尿病Wistar大鼠为受体,用体外低温保存状态下对供器官行腺病毒介导CTLA-4Ig基因转导制作异基因大鼠胰十二指肠移植动物模型.术后监测血糖,记录大鼠功能性存活期.术后3、10、17、28d经大鼠眶后静脉取血,应用ELISA法检测血清IL-2表达,Western blot检测人CTLA-4Ig的蛋白表达.结果 对照组大鼠功能性存活期为(11±1)d,转导组功能性存活期为(33±4)d(P＜0.01);对照组大鼠术后血清中未检测到人CTLA-4Ig蛋白表达,所有转导组存活病例,第10d血清中均有人CTLA-4Ig表达;转导组术后第3d、第10d血清IL-2分别为(33.710±7.803) pg/mL、(47.846±14.050) pg/mL,小于对照组(P＜0.01).结论 体外低温保存状态下对供器官行腺病毒介导人CTLA-4Ig基因转导,可以延长大鼠胰十二指肠移植术后功能性存活期,诱导免疫耐受.

Experimental Study on Immune Tolerance Induced by Human Ad-CTLA-4Ig in Rats with Pancreaticoduodenal Transplantation

OBJECTIVE: To study the immune tolerance induced by human Ad-CTLA-41g after pancreaticoduodenal transplantation of rats. METHODS: Wistar rats with diabetes were induced by caudal intravenous administration of streptozotocin (STZ) at a single dose of 60 mg/kg. Pancreaticoduodenal transplantations were performed with the SD rats as donors and the diabete Wistar rats as recipients. The SD pancreaticoduodenal grafts with human Ad-CTLA-41g infection via arterial perfusion in vitro were transplanted into Wistar rats with diabetes. The blood glucose of the rats was measured after transplantation. The graft functional survival time (GFST) was recorded. The concentration of IL-2 was measured by ELISA on day 3 and day 10 after operation. The human CTLA-41g was detected by Western blot after operation. RESULTS: The GFST of control group without gene transfer was (11+/- 1) d, while that of gene transfer group was (33 +/-4) d (P< 0. 01). The expression of serum human CTLA-41g was detected in rats of gene transfer group on the 10th day after transplantation, while no serum human CTLA-4Ig was detected in rats of control group without gene transfer. On the 3rd day after transplantation, the level of serum IL-2 was (33. 710+/-7. 803) pg/mL in rats of transfer group, and was (44. 772+/-9. 102) pg/mL in rats of control group without gene transfer. On the 10th day, the level of serum IL-2 was (47. 846+/-14. 050) pg/mL in rats of transfer group, and was (80. 806+/-18. 629) pg/mL in rats of control group without gene transfer. The levels of serum IL-2 in rats of transfer group was much lower than those of the control group without gene transfer (P