IGM, IGG, and IGA antibodies in human sera directed against porcine islets of Langerhans

Recently, clinical alloislet transplantations in human recipients with type I diabetes mellitus confirmed that insulin independence can be achieved. This clinical success will increase the demand for pancreatic grafts, but shortage may limit broad applications. Xenotransplantation might resolve the difficulty of organ availability, and therefore the use of porcine organs for transplantation is considered as an option. Concerning porcine islets, these are relatively easy to obtain with high yields of islets per pancreas and there is a close structural similarity between porcine and human insulin, so these islets may be the best alternative to human islets. The aim of the present study was to assess the presence of naturally occurring antibodies of the IgM, IgG, and IgA classes in normal human sera directed against porcine islets of Langerhans.