Reversal of diabetes by transplantation of cryopreserved rat islets of Langerhans to the renal subcapsular space.

Intraportal transplantation of cryopreserved islets of Langerhans has been shown to reverse streptozotocin-induced diabetes in rats. This study demonstrates the feasibility of transplanting 3,000 cryopreserved islets beneath the kidney capsule of syngeneic streptozotocin-diabetic Wistar-Furth rats. The clinical indices of plasma glucose, urine volume, and urine glucose returned to baseline values following implantation of fresh and cryopreserved islets. The clinical indices post-transplant and the K values (decline in plasma glucose concentration, percent/min) during intravenous glucose tolerance tests were not significantly different in rats receiving freshly isolated or cryopreserved islet grafts. The rapid return to the diabetic state after nephrectomy proved conclusively that the reversal of diabetes was due to the grafted islets. This was confirmed by immunocytochemical localization of well confirmed by immunocytochemical localization of well granulated islets beneath the kidney capsule. We conclude that cryopreserved islets reverse streptozotocin-induced diabetes after renal subcapsular implantation and that the clinical response is similar to fresh isografts.