Gastric mucosal secretion of interleukin-10: relations to histopathology, Helicobacter pylori status, and tumour necrosis factor-alpha secretion.

Interleukin-10 (IL-10) is an 18 kDa peptide with a range of anti-inflammatory and immunosuppressive properties. To determine whether this cytokine is involved in gastric mucosal inflammation in Helicobacter pylori infection. 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-alpha (TNF-alpha) content of supernatants was also determined in a subgroup of patients. 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-alpha, 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). Gastric mucosal production of IL-10 and TNF-alpha 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.