Xenotransplantation of neonatal porcine islets and Sertoli cells into nonimmunosuppressed streptozotocin-induced diabetic rats

The testis has been shown to be a privileged site for transplantation of allogenic islets in rodents, and the testicular cell aggregates are thought to confer this immunologic privilege. Recently, a group in Mexico reported transplantation of cocultured neonatal porcine islets and Sertoli cells resulting in insulin independence in nonimmunosuppressed type 1 diabetes patients. We have transplanted similar islets alone (naked islets) or cocultured islets with Sertoli cells (islet/Sertoli cells) into an omental site and other locations of nonimmunosuppressed, streptozotocin-induced diabetic male Sprague Dawley (SD) rats. Histologic examination showed viable neonatal porcine islets survived in xenografted rodents for at least 2 days, and some glucagon and inhibin stained cells appear to have survived for 4 days posttransplantation. However, histological examination did not demonstrate any difference in xenograft survival in the islets/Sertoli cells mixture compared to naked islets when transplanted into these nonimmunosuppressed diabetic rats.