The Effect of IL-26 on TNF-α-Induced CXCL8 Responses by Colonic Epithelial Cell Lines.

Th17 cells of the intestine and colon can produce several important cytokines during mucosal inflammation. However, few studies have focused on the role of IL-26 in intestinal inflammations. Colonic epithelial cells express receptors for IL-26, and this cytokine has been shown to induce the HT-29 colonic epithelial cell line to produce the chemokine CXCL8.

IL-22 Enhances TNF-α- and IL-1-Induced CXCL8 Responses by Intestinal Epithelial Cell Lines.

IL-22 is known to induce intestinal epithelial cells (IECs) to produce the chemokine CXCL8. However, IECs exist in a cytokine network during mucosal inflammation, such that IL-22 must act in concert with potent pro-inflammatory cytokines like TNF-α and IL-1. Our studies show that IL-22 alone increased CXCL8 secretion from HT-29 cells, but the levels were minimal compared to that of the cells treated with TNF-α or IL-1 only.