Interleukin‐8 production by the human colon epithelial cell line HT‐29: modulation by interleukin‐13

Abstract

We have determined which cytokines induce and modulate the production of the chemokine interleukin‐8 (IL‐8) by the human colonic epithelial cell line HT‐29. Growth arrested cell cultures were stimulated with the human recombinant cytokines interleukin‐1α (IL‐1α), tumour necrosis factor‐α (TNF‐α), interferon‐γ (IFN‐γ), interleukin‐13 (IL‐13), interleukin‐10 (IL‐10) or vehicle added alone or in combination. The production of IL‐8 was determined by enzyme‐linked immunosorbent assay (ELISA) and IL‐8 messenger RNA expression by Northern blot analysis. The production of IL‐8 in unstimulated cells was undetectable by both ELISA and Northern blot analysis. HT‐29 cells produced IL‐8 following stimulation with IL‐1α or TNF‐α in a time‐ and a concentration‐dependent manner, while IFN‐γ, IL‐10 and IL‐13 did not induce IL‐8 production by HT‐29 cells. IL‐13 was found to up‐regulate significantly (P < 0.01) the IL‐1α but not the TNF‐α‐induced IL‐8 generation by HT‐29 cells. In contrast, IL‐10 had no effect on either IL‐1α or TNF‐α‐induced IL‐8 production. Experiments using cycloheximide demonstrated that this synergistic effect of IL‐13 and IL‐1α on IL‐8 secretion was not through de novo protein synthesis. Using actinomycin‐D, we demonstrated that the IL‐13 up‐regulation was at the level of transcription rather than messenger RNA stability. These findings suggest that colonic epithelial cells have a functional IL‐13 receptor, which is coupled to an up‐regulation of IL‐1α, but not TNF‐α induced IL‐8 generation.

Lactobacillus plantarum Lipoteichoic Acid Alleviates TNF-α-Induced Inflammation in the HT-29 Intestinal Epithelial Cell Line

“…The synergic effect of both rhTNF-α and rhIFN-γ was not shown, indicating that IFN-γ does not affect the inflammation of intestinal epithelial cells while TNF-α modulates intestinal inflammation. These results are consistent with previously reported data (Erdman et al, 2009;Kolios et al, 1996). HT-29 cells stimulated with rhTNF-α increased IL-8 expression in a dose-dependent manner (Fig.…”

“…HT-29 cells produce IL-8 after stimulation by TNF-α and IL-1β, but not by IFN-γ, IL-10, or IL-13. TNF-α and nitric oxide (NO) trigger colonic inflammation and carcinogenesis in a Helicobacter hepaticus-infected mouse model, indicating that inflammation mediated by elevated TNF-α and NO causes colon carcinogenesis (Erdman et al, 2009;Kolios et al, 1996). Adhesion molecules, such as intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), are also implicated in cancer progression (O'Hanlon et al, 2002;Rosette et al, 2005).…”

Cytokine-induced Apoptosis in Epithelial HT-29 Cells Is Independent of Nitric Oxide Formation

“…Although markers of cytokine-stimulated apoptosis, such as DNA fragmentation and phosphatidylserine externalization, are detectable from 8 to 24 h, time course experiments have revealed that other functional responses continue unabated. For instance, identical cytokine treatment can also stimulate up-regulation of iNOS and chemokine mRNA up to 24 h post-stimulation (7,20) and these responses can be downregulated by pretreatment with IL-13 (7,8,10). So, cytokineinduced expression of apoptotic markers and events do not necessarily correlate with abrogated cell function, at least in the time frame studied here.…”

“…granulocyte/macrophage-colony stimulating factor and granulocyte-colony stimulating factor) expression by activated monocytes/macrophages or endothelial cells (1,6). Another target of IL-13 is epithelial cells and we have recently demonstrated that IL-13 can modulate chemokine generation from the human colonic epithelial cell line HT-29 (7,8) and inhibit iNOS expression and NO generation in this system (9). Activation of the signaling enzyme phosphatidylinositol 3-kinase (PI 3-kinase) by IL-13 is important for mediating these effects (8,10).…”

Intestinal inflammation modulates expression of 11β-hydroxysteroid dehydrogenase in murine gut

“…The cytokines TNF-a and IL-1b are known to increase 11HSD1 mRNA and 11-reductase activity in various cell types, such as glomerular mesangial cells (Escher et al 1997), osteoblasts , adipocytes (Tomlinson et al 2001), and aortic smooth muscle cells (Cai et al 2001). In addition, pro-inflammatory cytokines are important inducers of nitric oxide generation in macrophages and intestinal epithelial cells, and the interaction between the NO system and the 11HSDs has recently been demonstrated (Kolios et al 1996, Saito & Nakano 1996, Sun et al 1997, Ruschitzka et al 2001.…”