*Purpose: Islet transplantation is a promising treatment option for type 1 diabetes. Edmonton protocol recommended that over 30 % purity of islets is essential for successful transplantation. However, contamination of acinar cells cannot be prevented in the current procedure of islet isolation. The aim of this study is to clarify the influence of the islet purity in metabolic outcome of islet transplantation using intraportal islet transplant rodent model.

*Methods: We performed qPCR for inflammatory and oxidative stress-related cytokines which were derived from acinar cells and analyzed islet damage under co-culturing with acinar cells. Additionally, we transplanted 300 islets with acinar cells (1.0×10³, 1.0×10⁴, 1.0×10⁵ cells) and evaluated the influence of acinar contaminations to the outcome of transplantation.

*Results: Acinar cells upregulated inflammatory cytokine/chemokines RNA expression. TNFα and NOS were upregulated in islets co-culturing with acinar cells in comparison with islet alone. The therapeutic effect of islet transplantation in amelioration of blood glucose level was impaired by contamination of acinar cells. Acinar cells were found in sinusoid and portal vein at 3 hours after transplantation and patchy degenerative changes with infiltration of inflammatory cells were seen in the liver at 24 hours.

*Conclusions: The contaminated acinar cells in islet transplantation might induce inflammatory reaction in graft islet and hepatic parenchyma and worsen glycemic fluctuation in rodent model.

« Back to 2020 American Transplant Congress