Development of Novel Semipermeable Tubular Membranes for a Hybrid Artificial Pancreas

Abstract

Lack of normal insulin release by the pancreas may contribute to the long-term complications of diabetes. As an approach to restoring physiological insulin delivery, we are developing an implantable hybrid artificial pancreas consisting of pancreatic cells from islets of Langerhans cultured on the outside surface of semipermeable tubular membranes which are permeable to glucose and insulin but retain antibodies and lymphocytes. The device is implanted in the cardiovascular system as an arteriovenous shunt so that the cells have access to oxygen from the blood stream. The insulin-producing tissue is protected from the immune rejection process by the semipermeable membrane. This protection of the islet cells eliminates the problems associated with immunosupression which is required in ordinary transplantation procedures. Our approach offers the possibility of utilizing islet cells from animals in place of human tissue, and it relies upon natural biological feedback for insulin release and control of blood glucose concentration.