ABSTRACT
Objective To explore the function and survival of islet grafts during co-transplantation with adipose mesenchymal stem cells (AMSCs) in diabetic mice .Methods After human AMSCs and islet cells were isolated ,purified and then subcutaneously co-transplanted into nude mice with diabetes mellitus . Four groups of AMSCs + islet co-transplantation , islet transplantation alone ,phosphate buffered solution (PBS) and normal control mice were designated . Islet cell activity and apoptosis/revascularization degree of islet grafts were observed by immunohistochemical double staining of insulin ,factor associated suicide (Fas) and CD31 antibody . The blood glucose and serum insulin levels of mice and the survival time of islet grafts were compared . Results The blood glucose and serum insulin levels of diabetic mice analyzed by multivariate analysis in AMSCs + islet co-transplantation group were better than those in islet transplantation alone group (P< 0 .05 ) . The mean survival time (MST ) of islet grafts was longer in AMSCs + islet co-transplantation group than that in islet transplantation alone group [(81 .33 ± 7 .58) vs .(58 .17 ± 6 .91) days] (P<0 .05) .At Day 7 post-transplantation ,insulin staining intensity of islet grafts was higher in AMSCs + islet co-transplantation group than that in islet transplantation alone group while Fas staining intensity of islet grafts was lower .And mean microvascular density (MVD) of islet grafts per square millimeter was higher in AMSCs + islet co-transplantation group than that in islet transplantation alone group [(21 .8 ± 5 .6 ) vs . (14 .6 ± 4 .1 )] ( P< 0 .05 ) .Conclusions Co-transplantation with AMSCs may improve the function of islet grafts ,prolong its survival and promote its revascularization .
ABSTRACT
Objective To investigate the revascular and transplanted effects of islet grafts after co-transplantation with vascular endothelial cells ( ECs) in diabetic rats. Methods The rat ECs and islet cells were isolated and purified, then subcutaneously co-transplanted to the inbred SD male rats with diabetes mellitus, the group of islets transplanted alone, group of phosphate buffered solution, and group of normal rats served as control. Islet grafts revascularization degree, islet cells activity and apoptosis were observed by immunohistochemical double staining of CD31, insulin and factor associated suicide (Fas) antibody. The results of intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT), the blood glucose and insulin levels of the rats and the survival time of the islet grafts were compared. Results The blood glucose concentrations of IPGTT and IPITT, the blood glucose and insulin levels of rats analyzed by multivariate analysis in the ECs and islets transplantation group were better than those in the islets transplantation alone group (P<0.05). The islet grafts mean survival time of the ECs and islets transplantation group was longer than that of the islets transplantation alone group (P<0.05). On the 7th day after transplantation, mean microvascular density of islet grafts per square millimeter in the ECs and islets transplantation group was 26.4 ± 6.1, significantly greater than that in the islets transplantation alone group 18.3 ± 5.7 (P<0.05). In the ECs and islets transplantation group, insulin staining intensity was higher than that in the islets transplantation alone group (P<0.05), while factor associated suicide(Fas) staining intensity was lower than that in the islets transplantation alone group ( P<0. 05 ). Conclusion Co-transplantation with ECs could promote the revascularization of islet grafts and improve the effect of islet transplantation.