Immunological tolerance of rat pancreatic islet transplantation induced by transfusion of donor apoptotic splenocytes / 解放军医学杂志

ABSTRACT

Objective To investigate the effect of transfusion of allogeneic apoptotic splenocytes on immunological tolerance to pancreatic islets transplantation in rat. Method Recipient SD rats were rendered diabetic mellitus by a single intraperitoneal injection of streptozotocin (STZ). The apoptosis of donor Wistar rat splenocytes was induced by X-irradiation with electron linear accelerator. Pancreatic islets were isolated by intraductal collagenase P, and were purified by Ficoll-400 discontinuous density gradient after culturing for 1-2 days from donor Wistar rat. The diabetic SD rats were randomly divided into 4 groups, and respectively received infusion of Hanks solution, donor normal splenocytes, donor apoptotic splenocytes, and donor necrotic splenocytes via dorsal veins of penis, and then they received pancreatic islets from the same donor rat underneath their renal subcapsular space 7 days later. Mixed lymphocyte reaction (MLR) was used as immunological parameter of transplantation tolerance besides the observation of blood glucose level and allograft survival time. Islet graft failure was defined as the presence of a plasma glucose concentration of at least 11.0mmol/L on 2 successive days. Results The pre-infusion of donor apoptotic splenocytes significantly prolonged the survival time of allograft as shown by the median survival time (MST) of graft of 31days, and the longest survival time of 42 day, and it apparently decreased the rejection response in recipient SD rat in one-way mixed lymphocyte culture. Conclusion Transfusion of donor apoptotic splenocytes could induce immunological tolerance of allogenic islets transplantation in rat.