P236

Prevascularized bio-artificial PLGA device for subcutaneous islet transplantation

Jung Sik Kim^1,2, Hyun Ju Lim^1,2, Sang Joon Kim^1,2, Chung Gyu Park^1,3

¹Xenotransplantation Research Center, Seoul National University of Hospital; ²Department of Microbiology and Immunology, Seoul National University College of Medicine; ³Department of Surgery, Seoul National University of Hospital; Seoul, Korea

Subcutaneous site in clinical islet transplantation has been suggested strongly because of its surgical advantages. This site could minimize the unwanted blood-mediated inflammatory reactions which occasionally arose in intra-portal delivery of islets. However, clinical success of this site is limited by poor vascularization potential. To overcome this barrior, we constructed PLGA-based bioartificial device for promoting prevascularization in the subcutaneous site using hypoxia-preconditioned mesenchymal stem cells. PLGA device coated with hypoxia-preconditioned mesenchymal stem cells (HPLGA) supported the formation of vascularized structure inside and outside after the subcutaneous implantation, which was superior to PLGA device coated with normoxia-preconditioned mesenchymal stem cells (NPLGA). Maximum vascularization was observed between 4 and 5 weeks after implantation. As a result, when porcine islet mass (5,000 IEQ) was transplanted in the prevascularized-PLGA device, only HPLGA supported complete normoglycemic control. The amount of marginal mass which reverse hyperglycemia by 50% of transplanted-mouse was between 2000 IEQ and 3000 IEQ, which was comparable to that in kidney capsule. Therefore, prevascularized PLGA device might be a suitable alternative for the success of subcutaneous clinical islet transplantation.