Immunoprotection of rat islet xenografts by cotransplantation with Sertoli cells and a single injection of antilymphocyte serum

Background. Islet transplantation has become a clinical reality; however, before it can be extended to young juvenile diabetics an unlimited supply of tissue is needed and the use of chronic immunosuppression should be eliminated. This study was designed to determine whether Sertoli cells can immunoprotect islet xenografts. Methods. Lewis rat islets were cotransplanted with Balb/c Sertoli cells in diabetic Balb/c mice treated with one injection of anti-mouse lymphocyte serum (ALS). Results. When islets were transplanted alone, in combination with Sertoli cells, or in combination with ALS, mean graft survival times were 10.9+/-0.8, 14.0+/-1.2, or 12.2+/-0.7, respectively. When islets were combined with Sertoli cells and ALS, mean graft survival time increased to 64.9+/-8.1. Conclusions. Sertoli cells are able to prolong the survival of islet xenografts when combined with ALS, thereby supporting their use as a means to immunoprotect cellular grafts such as islets for the treatment of type 1 diabetes.