转基因骨髓间充质干细胞治疗鼠糖尿病的实验研究

目的 观察转人胰岛素基因的小鼠骨髓间充质干细胞（mMSCs）植入1型糖尿病小鼠肝脏对糖尿病的治疗作用。方法 分离绿色荧光蛋白（GFP）mMSCs,构建人胰岛素逆转录病毒载体,转染干细胞并移植到糖尿病小鼠肝脏。检测小鼠体重、血糖、血清胰岛素水平变化并作组织学分析。结果治疗组糖尿病小鼠6周内体重增加6％;血糖值在移植后7、42d分别为（10．4±2．8）mmol／L和（6．5±0．9）mmol／L,未经移植患病小鼠分别为（26．8±2．5）mmol／L和（25．4±4．1）mmol／L,二组间差异有统计学意义（P〈0．05）。治疗组小鼠血清及肝脏中检测到人胰岛素分泌。结论 肝内移植表达外源性胰岛素的mMSCs能有效降低糖尿病小鼠的血糖水平,缓解糖尿病症状,是一种糖尿病基因治疗的新途径。

Treatment of type 1 diabetes by transplantation of bone-derived mesenchymal stem cells expressing human insulin gene: experiment with mice

OBJECTIVE: To evaluate the effect of treatment of type 1 diabetes by transplantation of bone-derived stem cells expressing human insulin gene. METHODS: Murine bone marrow-derived stem cells expressing green fluorescent protein (GFP-mMSCs) were isolated from 4/6-week-old GFP mice and transfected with a recombinant retrovirus-murine stem cell virus (MSCV) encoding human insulin gene, thus constructing the GFP-mMSCs-MCV-insulin. 16 C57BL/6J mice were injected with streptozotocin so as to establish models of type 1 diabetes and then randomly divided into 4 equal groups: Group A, undergoing injection into the liver with GFP-mMSC-MCV-insulin 1 week after the establishment of the model, Group B, undergoing intrahepatic transplantation of the GFP-mMSCs transfected with blank vector, Group C, undergoing intrahepatic transplantation of untransfected GFP-mMSCs, and Group D, undergoing intrahepatic transplantation of phosphate-buffered saline (PBS). Another 4 normal mice were used as controls and underwent intrahepatic transplantation of PBS too. After the transplantation the blood glucose, serum insulin, and body weight were detected everyday. 6 weeks later immunohistochemistry was used to detect the expression of human insulin in the mice liver tissues. RESULTS: The body weight of Group A increased by 6% within 6 weeks after treatment, and the average blood glucose level 7 d and 42 d after transplantation were (10.4 +/- 2.8) mmol/L and (6.5 +/- 0.9) mmol/L respectively, both significantly lower than those of Group D (26.8 +/- 2.5) mmol/L and (25.4 +/- 4.1) mmol/L respectively, both P < 0.05]. Immunohistochemistry showed secretion of human insulin in serum and liver. CONCLUSION: The clinical manifestations of diabetes can be relieved effectively by intrahepatic transplantation of mMSCs expressing human insulin gene. This study implies a novel approach of gene therapy for type 1 diabetes.