IL-10 protects mouse intestinal epithelial cells from Fas-induced apoptosis via modulating Fas expression and altering caspase-8 and FLIP expression

Abstract

We have previously shown that the absence of Fas/Fas ligand significantly reduced tissue damage and intestinal epithelial cell (IEC) apoptosis in an in vivo model of T cell-mediated enteropathy. This enteropathy was more severe in IL-10-deficient mice, and this was associated with increased serum levels of IFN-gamma and TNF-alpha and an increase in Fas expression on IECs. In this study, we investigated the potential of IL-10 to directly influence Fas expression and Fas-induced IEC apoptosis. Mouse intestinal epithelial cell lines MODE-K and IEC4.1 were cultured with IFN-gamma, TNF-alpha, or anti-Fas monoclonal antibody (mAb) in the presence or absence of IL-10. Fas expression and apoptosis were determined by FACScan analysis of phycoerythrin-anti-Fas mAb staining and annexin V staining, respectively. Treatment with a combination of IFN-gamma and TNF-alpha induced significant apoptosis. Anti-Fas mAb alone did not induce much apoptosis unless cells were pretreated with IFN-gamma and TNF-alpha. These IECs constitutively expressed low levels of Fas, which significantly increased by preincubation of the cells with IFN-gamma and TNF-alpha. Treatment with cytokine or cytokine plus anti-Fas mAb increased apoptosis, which correlated with a decreased Fas-associated death domain IL-1-converting enzyme-like inhibitory protein (FLIP) level, increased caspase-8 activity, and subsequently increased caspase-3 activity. IL-10 diminished both cytokine- and anti-Fas mAb-induced apoptosis, and this was correlated with decreased cytokine-induced Fas expression, increased FLIP, and decreased caspase-8 and caspase-3 activity. In conclusion, IL-10 modulated cytokine induction of Fas expression on IEC cell lines and regulated IEC susceptibility to TNF-alpha, IFN-gamma, and Fas-mediated apoptosis. These findings suggest that IL-10 directly modulates IEC responses to T cell-mediated apoptotic signals.

IL-10 Prevents Apoptosis of Brain Endothelium during Bacteremia

“…7). Interestingly, although others have reported that the antiapoptotic effects of IL-10 are associated with upregulation of FLIP (CFLAR) (63,64), we found the opposite (Fig. 8, Tables II, III).…”

TNF-α/Cycloheximide-Induced Oxidative Stress and Apoptosis in Murine Intestinal Epithelial MODE-K Cells

“…TNF-α is a cytokine inducing apoptosis but many cell lines only undergo apoptosis when TNF-α is combined with an agent such as CHX. Previous observations in MODE-K cells showed that TNF-α per se in concentrations up to 10 ng·mL -1 and incubated for up to 24 h did not induce cell death [32].…”

Lentiviral-mediated multiple gene transfer to chondrocytes promotes chondrocyte differentiation and bone formation in rabbit bone marrow-derived mesenchymal stem cells

“…Regulation of apoptosis by IL-10 has been shown in other cell systems (33,34). IL-10 has recently been found to interfere with TNF-α-induced apoptotic pathways in epithelial cells and macrophages (35,36). Wang and Lou (37) indicated a direct protective effect of IL-10 from IL-1β-induced chondrocyte death.…”