激活型Akt1转染大鼠胰岛联合应用细胞毒T淋巴细胞相关抗原4免疫球蛋白延长异种胰岛移植存活

目的 观察激活型Akt1基因转染大鼠胰岛对异种胰岛移植功能和存活的影响.方法 提取大鼠胰岛培养转染,AO/EB和Tunel染色检测存活和凋亡;BALB/C糖尿病小鼠肾被膜下胰岛移植.分4组,实验组:Akt1转染胰岛联合应用细胞毒T淋巴细胞相关抗原4免疫球蛋白(CTLA-4Ig);Akt1组:移植Akt1转染的胰岛;未转染组:单纯胰岛移植,CTLA-4Ig组:单纯胰岛联合应用CTLA-4Ig;观察胰岛移植后功能存活时间和平均生存时间.结果 Akt1转染胰岛体外细胞抗凋亡生存率提高了25%;实验组移植物功能存活(32.5±6.6)d,平均生存时间(39.6±5.9)d比Akt1组(15.4±3.5)、(22.5±1.7)d和CTLA-4Ig组(18.7±4.5)、(21.7±3.5)d未转染组(4.5±2.8)、(6.8±3.1)d明显延长(P<0.05).结论 激活型Akt1转染大鼠胰岛联合应用CTLA-4Ig,可减少移植胰岛凋亡,延长异种胰岛移植物存活时间.

Influence of constitutively active Akt1 gene in combination with CTLA-4Ig on xeno-islet transplantation in diabetic mice

Objective To explore the effects of transfection of constitutively active Akt1 into rat islets on xeno-islet transplantation. Methods Rat islets were separated and purificated, and then trans-leered with Adv-CA-Akt1. AO/EB stain was used to examine the survival, and TUNEL test to detect the apoptosis of islets. And 300 IEQs islets were transplanted under the kidney capsule of BALB/C diabetic mice. The mice were divided into 4 groups in random. In experimental group, transfection of Akt1 gene into islets in combination with intraperit0neal injection of CTLA4Ig;in Akt1 group:transfeetion of Akt1 gene in-to islets only; in CTLA4 Ig group: intraperitoneal injection of CTLA4Ig only; in nontransfected group : simple islet transplantation. Blood glucose level and graft survive time were determined. Results The islets with Akt1 gene gained more ability to survive in vitro, and apoptosis ratio was decreased by 25%. In experimen-tal group, the glucose level was decreased and normal in longer term ( 32.5±6.6 ) days, and the life splan ( 39.6 ± 5.9) days was longer obviously than the other groups Akt1 group: ( 15.4 ± 3.5 ), (22.5 ± 1.7 ) days; CTLA-4Ig group: ( 18.7 ± 4.5 ), ( 21.7 ± 3.5 ) days; nontransfected group : ( 4.5 ± 2.8 ), ( 6.8± 3.1 ) days,P < 0.05]. Conclusion Akt1 gene in conbination with CTLA-4Ig is an attractive target for fu-ture strategies aimed at decreasing islet apoptosis and prolonging the life span effectively in xeno-genic islet transplantation.