Cold-preservation of pancreatic beta cells

Area of Science:

• Islet cell transplantation
• Graft preservation
• Beta cell biology

Background:

• Clinical islet transplantation necessitates effective graft preservation to minimize viable beta cell loss.
• Current preservation methods often result in significant beta cell loss during storage.

Purpose of the Study:

• To evaluate the survival and function of rat pancreatic beta cells during prolonged cold storage (96 hours at 4°C).
• To identify optimal preservation solutions for maintaining beta cell viability and function for transplantation.

Main Methods:

• Assessing beta cell viability using single cell assays after storage in various solutions (HAM's F10, UW, Collins, CAB).
• Evaluating beta cell aggregates using DNA recovery and electron microscopy after storage in CAB solution.
• Measuring insulin content and glucose-stimulated insulin release from stored beta cells.
• Assessing functional recovery after transplantation of cold-stored islets into diabetic rats.

Main Results:

• Less than 20% beta cell viability was observed after 48h in HAM's F10 medium.
• Collins solution supplemented with albumin and benzamidine (CAB) improved viability to 77% after 96h at 4°C.
• Beta cell aggregates showed good preservation in CAB solution, with preserved insulin content and comparable glucose responsiveness post-storage.
• Transplantation of CAB-stored islets corrected hyperglycemia in diabetic rats.

Conclusions:

• Rat beta cells can be stored for at least 4 days at 4°C in CAB solution, maintaining cell number, hormone content, and glucose responsiveness.
• This cold storage method is equivalent to 20°C or 37°C culture for short-term preservation.
• Further research is needed to determine the long-term benefits of CAB solution for islet cell grafts.