ECD for islet transplantation

Pancreatic islet transplantation offers a minimally invasive option for type 1 diabetic patients. Before 2000, less than 10 % of the recipients of islet transplantation achieved insulin independency [1]. The introduction of the Edmonton Protocol, however, with a highly improved rate of insulin independency, encouraged us to promote clinical islet transplantation [2, 3]. In the Edmonton Protocol, brain-dead donors were used for islet isolation, and the donors were selected according to the factors that influence the success of islet isolation [4]. Even using the Edmonton Protocol, the results of clinical islet transplantation including a long-term graft survival were far from ideal and were significantly worse than clinical pancreas transplantation (pancreas transplant alone, PTA). The newly designed protocol from Minnesota University by Hering et al. that includes induction therapy with a T-cell-depleting antibody (anti-thymus globulin, ATG) and an inhibitor of tumor necrosis factor-α (TNF-α) achieved successful islet transplantation from a single donor. Short-term and long-term islet graft survivals were shown which were comparable to those in clinical pancreas transplantation (PTA). These results demonstrated that islet transplantation was expected to take the place of solitary pancreas transplantation for the type 1 diabetic patients without renal dysfunction. Strict donor criteria are not necessarily needed for islet transplantation because the islets were transplanted after its evaluation after isolation, which is different from pancreas transplantation in which the pancreas is transplanted to the recipients immediately after procurement from the donor. Therefore, extended criteria donor has not been clearly defined in islet transplantation. DBD donors were most frequently used for islet transplantation worldwide. In our country, however, DCD donors were used for islet transplantation because of an ultimate shortage of DBD donors and the regulation under Organ Transplantation Law that was enforced in 1997. Although a clear definition as an extended criteria donor for islet transplantation has not been determined, the factors that influence the outcome of the islet isolation were investigated in previous papers. In this chapter, the factors that influence the outcome of the islet isolation were introduced and extended criteria donor for islet transplantation is discussed.