转染血管内皮生长因子165基因对胰岛移植物血管再生及移植效果的影响

Revascularization and transplantation effect of transfecting VEGF16s gene to islet grafts

目的 探讨转染血管内皮生长因子165（VEGF165）基因对胰岛移植物血管再生及移植效果的影响.方法 将含有VEGF165基因的慢病毒-VEGF165 （LV-VEGF165）体外转染大鼠胰岛细胞,移植于近交系SD雄性糖尿病大鼠肾包膜下,设未含有VEGF165基因的LV-AcGFP1为空载体对照组（LV-AcGFP1组）和单独胰岛细胞为空白对照组.ELISA检测VEGF165的体内外表达,胰岛素、CD31免疫组化双染观察胰岛移植物血管化程度及胰岛细胞活性,并比较各组糖尿病大鼠血糖、胰岛素水平及胰岛移植物存活时间.结果 LV-VEGF165组胰岛细胞体内外分泌的VEGF165浓度均显著高于LV-AcGFP1组和空白对照组（P＜0.01）.免疫组化检测LV-VEGF165组每平方毫米胰岛移植物平均微血管密度（MVD）为（24.3±3.7）,显著大于LV-AcGFP1组（12.4±2.5）及空白对照组（12.7±2.1,P＜0.01）,胰岛素染色强度于LV-VEGF165组高于LV-AcGFP1组及空白对照组.多元分析糖尿病大鼠血糖、胰岛素水平,LV-VEGF165组优于LV-AcGFP1组和空白对照组（P＜0.01）;LV-VEGF165组胰岛移植物于移植术后平均生存时间（MST）经log-rank检验长于LV-AcGFP1组及空白对照组（P＜0.01）.结论 转染VEGF165基因具有促进胰岛移植物的血管再生及提高胰岛移植效果的作用.

Objective To investigate the influence of VEGF165 gene transfection on the revascularization and transplantation effect of islet grafts.Methods The rat islet cells were transfected with lentivirus containing VEGF165 gene （LV-VEGF165） in vitro,then transplanted to the renal capsule of inbred SD male rats with diabetes mellitus.Islet cells transfected with lentivirus marked with AcGFP1 and no VEGF165 gene were set as null vector control group （LV-AcGFP1 group）,individual islet cells as blank control group.VEGF165 expression in vivo and in vitro was detected by ELISA.The islet grafts revascularization degree and islet cell activity were observed by immunohistochemical double staining of insulin and CD31 antibody.Blood glucose and insulin level of rats with diabetes mellitus and survival time of islet grafts were compared.Results The VEGF165 concentrations in the LV-VEGF165 group secreted by islet cells in vivo and in vitro were significantly higher than those in the LV-AcGFP1 group and the blank control group （P〈0.01）.Mean microvascular density （MVD） of islet grafts per square millimeter in the LV-VEGF165 group was （24.3 ± 3.7）,significantly greater than that in the LV-AcGFP1 group （12.4 ± 2.5） and the blank control group （12.4 ± 2.5） （P〈 0.01）.Insulin staining intensity in the LV-VEGF165 group was also higher than that in the LVAcGFP1 group and the blank control group.The blood glucose and insulin levels in rats with diabetes mellitus analyzed by multivariate analysis in the LV-VEGF165 group were controlled more effectively than those in the LV-AcGFP1 group and the blank control group （P〈0.01）.The islet grafts mean survival time （MST） after transplantation in the LV-VEGF165 group was longer than that of the LVAcGFP1 group and the blank control group （P〈0）.01）.Conclusion The VEGF165 gene transfection to islet cells could promote the revascularization of islet grafts and improve the effect of islet transplantation.