The Syngeneic Islet Transplantation to Study Physiology and Pathophysiology of Pancreatic β-Cells

Abstract

Several years ago, techniques have been developed for isolation of pancreatic islets from rodent pancreas^1,2 in order to permit in vitro studies on the mechanism and events involved in the formation, storage, and release of insulin by pancreatic B-cells and other hormones produced by the islet cells³. A natural outgrowth of this development was to determine whether transplants of isolated islets into inbred strains of rodents (syngeneic transplantation), with experimentally induced diabetes, would achieve and maintain normoglycaemia in the recipients. Since the pioneering work of Lacy⁴, who demonstrated the successful reversal of diabetes with syngeneic islet grafts, studies were performed to determine the effect on diabetic complications, as they occur in rodents. The islet transplants prevented or reversed many of the complications caused by hyperglycaemia, thus the possibility was raised to utilize pancreatic islets for transplantation in diabetic patients^4–6. In consequence, primary experimental, and later clinical research was concentrated on the development of methods for mass isolation of islets, for immunological procedures, which allowed allogeneic or xenogeneic transplantation without continuous immunosuppression, and for clinical application in diabetic patients. Even, if the ultimate goal of islet transplantation is to cure diabetic patients, the syngeneic islet transplantation can be used to improve our understanding of pancreatic B-cells in normal and abnormal conditions. This review will summarize some results obtained when fetal, neonatal or adult pancreatic islets were grafted into inbred animals.