Regulation of mhc protein expression in pancreatic β-cells by lnterferon-γ and tumor necrosis factor-α

Abstract

Isolated human and mouse pancreatic islet cells and the rat insulinoma cell line RIN-m5F were used to examine the ability of recombinant interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) to regulate the expression of the class I and class II major histocompatibility (MHC) surface proteins and mRNA in β-cells. Each cytokine increased significantly the expression of class I MHC proteins as determined by double indirect immunofluorescence microscopy and flow cytofluorimetric analysis. In the RIN-m5F cells, this increase in surface expressed class I MHC proteins was mirrored by an increase in the level of class I MHC mRNA. The order of potency of the cytokines on class I MHC expression wa..