The pancreatic islet is a microorgan composed of four types of hormone-producing cells. In the human pancreas, the islets comprise about l–2%; of the pancreatic mass, and the islet number is approx 1−2 � 106 . The majority of cells, which are mainly located in the center of the islet, are the insulin-producing �;β-cells In the periphery, α-cells and δ-cells synthesizing glucagon and somatostatin, respectively, are found. Finally, a small number of cells containing pancreatic polypeptide (PP) are scattered within the islets (1 ). In addition, in the intact pancreatic islet nerve cell fibers, vascular tissue as well as a few residing immune cells can also be observed. Owing to the requirements to study the in vitro function of the �;cells for various aspects of diabetes research, methods have been developed to isolate and culture free pancreatic islets
