Background: Islet of Langerhans' cell transplantation is a promising strategy for the treatment of type-1 diabetes mellitus. Results of this procedure have yet to match those of whole organ pancreas transplantation, but are rapidly improving, as witnessed by increasing rates of insulin independence and graft function (i.e., C-peptide production) after islet transplantation.
Discussion: Identification of obstacles to the success of islet transplantation, such as primary nonfunction, immunosuppression-related metabolic workload, or recurrence of autoimmunity, will allow the development of new strategies tailored to overcome them. In particular, novel immunosuppressive protocols, with or without the aim of inducing tolerance, and immunoisolation devices are reaching the stage of clinical applicability. Finally, several strategies, such as utilization of porcine xenogeneic islets or genetically engineered beta-cell lines, or in vitro expansion of cultured beta-cells could theoretically expand indefinitely the pool of islet tissue for transplantation.