Advances in the Use of Biologics and Biomaterials toward the Improvement of Pancreatic Islet Graft Survival in Type 1 Diabetes

Islet transplantation is a curative treatment for patients suffering from type 1 diabetes and has the potential to replace current treatment strategies involving the exogenous administration of insulin. Despite this potential, there are many hurdles in achieving successful long-term graft survival due to autoimmune and foreign body reactions leading to graft rejection coupled with donor shortage and potential adverse effects from the need for long-term administration of immunosuppressive drugs. As a result, various approaches have been proposed to increase the viability and function of islet grafts during isolation and ex vivo culture with the use of growth factors, hormones, and other therapeutic agents. In addition, other strategies have addressed how to enhance or maintain islet graft performance after implantation with improvements on immunosuppressive drug regimens and the use of biomaterials to encapsulate and protect the cells from graft rejection. This review focuses on the recent advances in strategies to improve islet viability and function with the addition of exogenous compounds and the implementation of conformal coating as a promising tool for immunoprotection of islet transplants.