Inhibition of IFN-gamma activity in supernatants from stimulated human intestinal mononuclear cells prevents up-regulation of the polymeric Ig receptor in an intestinal epithelial cell line.

摘要: The polymeric IgR (pIgR) mediates transcytosis of IgA across mucosal epithelia. Expression this receptor in HT-29.74 human colon carcinoma cells is up-regulated by the recombinant cytokines IFN-gamma, TNF-alpha, and IL-4. Here, we demonstrate that activation freshly isolated intestinal lamina propria mononuclear (LPMC) induces production natural cytokines, these act synergistically as potent stimulators pIgR expression cells. LPMC from normal colonic mucosa were stimulated with PMA calcium ionophore A-23187. resulting supernatants consistently induced dose-dependent increases cells, up to 65-fold. Analysis four separate revealed mean concentrations 8260 pg/ml for 420 15 Ab-mediated neutralization suggested central regulator was IFN-gamma. IL-4 had no effect on induction TNF-alpha slightly reduced induction. In contrast, IFN-gamma abolished 93% essentially same simultaneous all three cytokines. conclusion, our data predominantly produced lymphocytes macrophages have capacity up-regulate dramatically an epithelial cell line, strongly suggesting their action vivo leads enhancement local defense functions mediated IgA.