Study On The Induction Of Islet Transplantation Tolerance In Mice By Allogeneic Antigen-specific CD4～+CD25～+ Regulatory T Cells And Its Mechanisms

Isolation and transplantation of mouse pancreatic islets Objectives: To study the methods and influencing factors for effective isolation and transplantation of mouse pancreatic islets. Methods: Islets were digested by pancreatic ductal injection of collagenase and purified by Histopaque 1077 density centrifugation method. Glucose stimulated insulin secretion test was performed to evaluate the function of isolated islets in vitro. Islet cultured with different time periods was allogeneically transplanted under the kidney capsule of streptozotocin-induced diabetic BALB/cByJ mice to evaluate the function of isloated islets in vivo.Results: Mice with a higher weight showed a higher islet yield than lower weight mice (166.5 ± 23.47 vs 89.83 ± 7.65; P < 0.01). Islet viabilities were more than 95%. Islet yield varied with application of different concentrations of collagenase, the time and temperature during digestion. Insulin secretion of isolated islets was good both in vitro and in vivo. Short-time culture (12～24 h) of isolated islets showed better survival than tant cultured for 2～4 h. However, there was no difference between the two groups in glucose stimulated insulin secretion. Conclusions: The weight of the donor mouse, the concentration of...