Strategies toward single-donor islets of Langerhans transplantation

Purpose of review The current review addresses a critical need in clinical islet transplantation, namely the routine transition from the requirement of two to four donors down to one donor per recipient. The ability to achieve single-donor islet transplantation will provide many more islet grafts for treatment of an ever-expanding patient base with type 1 diabetes (T1DM) with poor glycemic control. Avoiding exposure of recipients to multiple different donor human leukocyte associated (HLA) antigens is critical if risk of donor sensitization is to be avoided. This point is important as further islet or pancreas transplants in the remote future or the potential future need for a solid organ kidney transplant may become prohibitive if the recipient is sensitized. Recent findings This review addresses systematically all areas that contribute to the success or failure of single-donor islet engraftment, beginning with donor-related factors, optimizing islet isolation and culture conditions, and describes a series of strategies in the treatment of the recipient to prevent inflammation, apoptosis, islet thrombosis, and improve metabolic functional outcome, all of which will lead to improved single-donor engraftment success. Summary If single-donor islet transplantation can be achieved routinely, therapy will become more widely available, more accepted by the transplant community (currently pancreas transplantation requires only a single donor), and this situation will have a major impact overall as an effective treatment option in T1DM.