Objective: To study potential mechanisms of DST(donor-specific transfusion) prolonging pancreas allograft survival in the rat model. Methods: Outbred wistar male rats were used as blood and pancreas donor and diabetic recipients. Diabetic recipients were divided into two groups: control and DST group. Whole pancreas transplantation in abdomen were performed with pancreatic ductopen. Two groups of rats were killed for 7 days after transplantation. Grafted pancreas were stained with Hematoxylin and eosin stain method. Islets were stained with Gomori modified aldehyde fuchsin stain method. Alkaline phosphatase enzyme immunoassay method was used to detect lymphocyte and cytokines in allografts. Results: Analysis of grafts showed that both control and DST rats had lymphocytes infiltrates

higher percentage of CD+4 T cells in DST group and higher percentage of CD+8 T cells in control group. There was no evidence of pancreas and islet injury in DST rats. Grafts in control rats were characterized by pancreas and islet injury and expression of IL-2

TNF-α. Conclusion: These results indicated that DST prolonging pancreas allograft survival was associated with decreasing expression of IL-2

TNF-α in grafts.