VIABILITY OF ISOLATED AND CULTURED LANGERHANS ISLETS OF RAT

Background: Many researches have been conducted on islet cells' transplantation for a definitive treatment of diabetes mellitus type1. As the viability of the islets is the most important factor in predicting the transplantation prognosis, we have designed a study to isolate rat's islets. The aim of the study was to assess the viability of the islets at different stages and suggest the best transplantation time. Methods: Pancreatic islets were isolated from male rats (250-300gr) by standard surgical procurement followed by intraductal HBSS distension, chopping and digestion with collagenase (type V). After being centrifuged for 3 times, the islets were then hand-picked and incubated in 37 o C with RPMI 1640 media for 6 days. Each well contained 35-45 islets. Viability of islets was assessed by 2 independent investigators, giving score 0-2 to the color of islets under florescent microscope after Propidium iodide/Acridine orange staining at 6 times: just after the incubation, 24h, 48h, 3rd day, 5th and 6th day. Results: The viability of the islet cells was gradually increased after the incubation as we had the most viability rate after the second day, while it decreased after this period and reached  the least rate on the 5 th and 6 th day. Conclusion: The islets' viability increased following the cell culture after the isolation procedure, as they have the best condition for transplantation after 48 hours. As the islets' viability is the most critical point in transplantation, further studies evaluating the effects of different interventions on viability is needed.