Prolongation of islet allograft survival in rats by cotransplantion with xenogenetic neonatal porcine Sertoli cells

Abstract

Objective To investigate whether cotransplant with xenogenetic neonatal porcine Sertoli cells (NPSCs) could prolong rat islet allograft survival and its mechanisms.Methods 1500 islets equivalent quantity (IEQ) and 1×10~7 NPSCs were implanted under renal capsule of diabetic Wistar rats.Islets implanted alone were used as control group (n=6);islets co-transplanted with NPSCs under left renal capsule of recipients served as experimental group (n=6);meanwhile,islets and NPSCs implanted into the different sides of kidneys were used as another control grouP(n=4).Blood glucose level was measured everyday.The graft-bearing kidneys at the time of rejection were Results Co-transplantation with NPSCs to the same site significantly prolonged islet allograft survival (mean survive time,16.3±1.4 days vs.5.7±1.0 days in islet transplant alone control group,P<0.05).In contrast,transplantation with NPSCs and islets separately did not prolong the islet allograft survival (5.3±0.5 days).HE staining showed plenty of local infiltrated lymphocytes in the transplanted site of the eontrol group.which were demonstrated as mainly CD3+ T cells by immunopathology.The local expression of Bcl-2 was markedly elevated in co-transplantation group as compared with the other 2 groups,while there were no significant differences in the HO-1 expression among these groups.Conclusion Co-transplantation with xenogenic NPSCs can significantly prolong islet allograft survival in rats.The immunoprotective mechanism may be associateel with the inhibition of lymphocyte infiltration and the enhancement of the local expression of protective gene Bcl-2. Key words: Sertoli cell; Islets of Langerhans; Transplantation; Genes,bcl-2; Heme oxygenase