Gastric mucosal secretion of interleukin- 10: Relations to histopathology, Helicobacter pylori status, and tumour necrosis factor-α secretion

Abstract

Background-Interleukin-10 (IL-10) is an 18 kDa peptide with a range of anti-inflammatory and immunosuppressive properties. Aim-To determine whether this cytokine is involved in gastric mucosal inflammation in Helicobacter pylori infection. Methods-The production of IL-10 by antral mucosal biopsy specimens during short term in vitro culture was determined by measuring IL- 10 content of supernatants by enzyme linked immunosorbent assay (ELISA). H pylori status was determined by serology and histology, with gastritis scored using the Sydney system. Tumour necrosis factor-α (TNF-α) content of supernatants was also determined in a subgroup of patients. Results-IL-10 secretion was significantly greater in patients with H pylori associated chronic gastritis than in patients who were H pylori negative with normal mucosa/reactive changes, and those with H pylori negative chronic gastritis (p<0.01 and <0.05 respectively). There was a significant correlation overall between IL-10 secretion and chronic inflammation score (r=0.40). Secretion of TNF-α, which was significantly higher in H pylori infected patients than uninfected patients with a normal mucosa (p<0.04), correlated with scores for chronic inflammation and activity (r=0.39 and 0.38 respectively), but was only weakly correlated with IL-10 secretion (r=0.22, NS). Conclusions- Gastric mucosal production of IL-10 and TNF-α are increased in chronic gastritis associated with H pylori infection, and mucosal cytokine secretion varies with important histopathological aspects of gastric inflammation. Whereas the secretion of IL-10 in H pylori infection may be protective, limiting tissue damage caused by inflammation, it may also contribute towards failure of the immune response to eliminate the organism.