Islet xenotransplantation

Purpose of review This paper will review the recent experimental and clinical data on islet xenotransplantation focusing on the pig as an islet donor. Recent findings The review addresses the issue of why achieving successful islet xenotransplantation is so important for the future treatment of diabetes. It describes in detail the immunology behind islet xenotransplantation and reviews three different techniques being used to overcome the immunological barriers to islet xenotransplantation. Microencapsulation of the porcine islet has recently resulted in two different groups reporting prolonged survival in pig to primate islet xenografts. Using co-stimulation blockade as part of an immunosuppressive regime has been shown by two groups to allow reversal of diabetes for up to 6 months with pig to primate islet xenografts. Finally one group has co-transplanted porcine islets and Sertoli cells into diabetic patients and report continuing function at four years post transplant. Summary Recent developments in islet xenotransplantation give great encouragement that this can be developed into a safe and widely applicable therapy for diabetes.