Preparation of Immunotolerant Space Under the Skin and Transplantation of Islets in the Space.

Although transplantation of islets of Langerhans has been accepted as a fundamental treatment for insulin-dependent diabetes mellitus (IDDM), several problems are still remaining in order that it becomes the standard medical treatment of IDDM patients. In this study, using diabetic rat models, a subcutaneous space surrounded with highly vascularized granulomatous tissue was formed by agarose-bFGF rod implantation. Allogeneic islets transplanted into the space could survive and release insulin for a long period under no immunosuppressive medication. In conjunction with sufficient supply of islets from iPS/ES cells, our method can make islet transplantation the standard medical treatment of IDDM patients.