Expression of proinflammatory and Th1 but not Th2 cytokines is enhanced in gastric mucosa of Helicobacter pylori infected children.

BACKGROUND

Helicobacter pylori-induced gastric inflammation is thought to be largely regulated by cytokines.

PATIENTS AND METHODS

The expression of interferon-gamma, interleukin-12, interleukin-4, interleukin-10, interleukin-8, and interleukin-17 mRNA was examined on gastric mucosal samples from 24 children by semiquantitative reverse transcription polymerase chain reaction and southern blotting. Biopsy-based tests, serology, and urea 13C breath test were used to assess Helicobacter pylori status. Gastric biopsies were also evaluated for bacterial density, chronic inflammation, and acute inflammatory activity.

RESULTS

Interferon-gamma, interleukin-12, interleukin-8 and interleukin-17 expression was higher in Helicobacter pylori-infected (n=13) than uninfected (n=11) children. Conversely, interleukin-4 and interleukin-10 expression did not differ between Helicobacter pylori-infected and uninfected children. In Helicobacter pylori-infected children, interferon-gamma, interleukin-12, interleukin-8 and interleukin-17 expression correlated with bacterial density, and Interferon-gamma and interleukin-12 expression with chronic inflammation score.

CONCLUSIONS

The findings of this study indicate that, in children, Helicobacter pylori-induced inflammatory response would favour production of proinflammatory cytokines and development of cell-mediated immunity, namely Th1 response.