Transplantation of NIT-1 cells with ectopic FADDdelGFP expression for treatment of streptozotocin-induced diabetes

Islet transplantation is considered a therapeutic option for type 1 diabetes (T1D). However, allorejection is one major barrier for the successful islet transplantation. In the present study, we have tested the feasibility of a deletion construct for Fas-associated death domain protein (FADD; without the death effecter domain) fused with green fluorescent protein (FADDdel-GFP) for blocking the Fas-FasL signaling pathway in prevention of transplanted beta cell destruction by allorejection in T1D. In vitro studies have shown that NIT-1 cells with ectopic FADDdel expression were resistant to cytokine-induced apoptosis and CTL-mediated lysis. Diabetic Balb/c mice reached normoglycemia promptly and gained weight after transplantation of NIT-1 cells with ectopic FADDdel-GFP expression. These recipients showed a significant longer survival time than that of recipients transplanted with NIT cells with ectopic GFP expression only. Our results together suggest that FADDdel could be a useful target for the improvement of islet transplantation for T1D.