The Ideal Transplantation Site And Dose-effect Relationship Of Insulin Gene Transfected Bone Marrow-derived Mesenchymal Stem Cells In Treating Diabetic Mice

Objective: To observe the ideal transplantation site and the dose-effect relationship of insulin gene transfected bone marrow-derived mesenchymal stem cells(BM-MSCs) in treating diabetic miceMethods: 1.C57BL/6J mice were given intraperitoneal injection with different dose of STZ to make diabetic models. We observed the relationship between stability of diabetes models and STZ dose. 2.BM-MSCs of GFP-mice were transfected by insulin gene with the recombinant retrovirus INS-MSCV. After cultivation in vitro, we performed 5×106 transfected cells transplantation in stable diabetic mice which were divided into 5 groups(n=5) with the transplantation site of hepar, kidney, pancreas, spleen and caudal vein separately. According to blood glucose, body weight and histological sections detection,etc, we discuss the ideal transplantation site.3.10 groups of stable diabetic mice(n=5) were performed transplantation in the ideal site with the cell dosage of 1×104,5×104,1×105,5×105,1×106,5×106,1×107,5×107,1×108,5×108 separately. We observed the relationship between cell dose and post-transplant blood glucose concentration.Results:2.With the STZ dose of 80-180mg/kg, the diabetes mice models were stable. From the 20th day after STZ injection, the blood glucose concentration kept steady, and the 45-day-survival rate was higher than 80%. 2.Hepar is the best transplantation site of insulin gene transfected BM-MSCs. On the 45th day after transplantation, blood glucose concentration of Hepar group decreased to 6.3±1.3mmol/L; body weight increased to 22.2±0.4g; serum insulin level increased to 19.9±1.5μU/ml. Compared with other groups', these differences were significant(P<0.05). Through pathological observation, the graft survival and insulin expression in liver tissues were confirmed.3.The cell dose is inversely correlated with post-transplant blood glucose. When the transplantation site was hepar and the transplantation dose interval was [5×104,5×108], the curvilinear equation between cell dose(X) and the post-transplant blood glucose concentration(Y) was Y=66.574-14.227lgX+ 0.852(lgX)2.Conclusions: 1.80-180mg/kg of STZ dose range is ideal for making stable diabetes C57BL/6J mice models. 2.Insulin gene transfected BM-MSCs transplantation can efficiently treat diabetic animals and the ideal site was hepar. 3. The effect of insulin gene transfected BM-MSCs transplantation is positive correlated with cell dose in a certain range.