AN OVERVIEW OF THE EXPERIMENTAL ISLET ISOLATION IN HUMAN PANCREAS

Type 1 diabetes mellitus (T1DM) is a disease caused by autoimmune destruction of the pancreatic beta cells. Allogeneic islet transplantation is recommended for “brittle T1DM patients “as intensive insulin therapy seems to be associated with an increased incidence of hypoglycemia. The aim of this article was to describe the studies on human islet isolations verified in the Diabetes Application and Research Center (DIYAM) in Istanbul University. Pancreas were harvested from brain-dead donors and stored at -80°C. Media preparation [dilution, priming, wash, final wash, decontamination and gradient purification solutions, University of Wisconsin (UW) pre-purification media]; instrument set-up (dissection/perfusion and dissociation systems); distension [pancreas preparation (trimming and rinsing of the pancreas, cannulation into the pancreatic duct)]; making enzyme solution (reconstitution of enzyme, dilution of enzyme solution, filtration of diluted enzyme solution); perfusion (perfusion to distend pancreas with enzyme solution); dissociation (pancreas digestion, digested tissue collection); recombination and purification (using COBE 2991cell processor) were the main phases of islet isolations. As the primary goal of isolating the pancreatic islets for either in vivo transplantation or in vitro studies is to achieve a large amount of viable islets, also viability experiments both in vitro and in vivo using experimental animals were realized in these studies. An average of 300,000 islets were obtained after purification. We suggest that improvement in amount and viability of isolated islets after long-term storage can be achieved when appropriate storage solutions and new types of enzymes would be used, and in the near future DIYAM would be among islet transplantation centers worldwide by starting auto-transplantations of islets of Langerhans for mantaining insulin production and secretion in pancreotectomized patients.