FADDdel-GFP modified mouse insulinoma cells counteract the cytotoxicity of reactive T cells.

IDDM results from pancreatic beta cell destruction by islet-reactive T cells, a process that involves beta cell apoptosis. Fas-FasL pathway plays a major role in pancreatic beta cell death. Fas-associated death domain protein (FADD), the component of the tumor necrosis factor receptor type 1 (TNFR1) and Fas signaling complexes, is involved in TNFR1- and Fas-induced apoptosis. Inhibiting the function of FADD will lead to blocking downstream apoptosis signal, which protects pancreatic beta cells from destruction by Fas-FasL pathway. In this study we constructed eukaryotic expressing vector of fusional protein FADDdel-GFP named pFADDdel-GFP. After pFADDdel-GFP was transfected into NIT, the expression of FADDdel-GFP in NIT was detected by fluorescence microscopy and the resistance of NIT transfected with pFADDdel-GFP to cytotoxicity mediated by special T cells was detected by FACS and MTT. The results showed that NIT modified by pFADDdel-GFP obviously resisted cytotoxicity mediated by special T cells. Therefore, it may be useful in the prevention or treatment of IDDM by intervening Fas-FasL pathway.