Expression of proinflammatory and Th1 but not Th2 cytokines is enhanced ingastric mucose 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 in terleukin-4, interleukin-10, interleukin-8, and interleukin-17 mRNA was exa mined on gastric mucosal samples from 24 children by semiquantitative rever se transcription polymerase chain reaction and southern blotting. Biopsy-ba sed tests, serology, and urea C-13 breath test were used to assess Helicoba cter pylori status. Gastric biopsies were also evaluated for bacterial dens ity, 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 uninfec ted (n = 11) children. Conversely, interleukin-4 and interleukin-10 express ion did not differ between Helicobacter pylori-infected and uninfected chil dren. In Helicobacter pylori-infected children, interferon-gamma, interleuk in-12, interleukin-8 and interleukin-17 expression correlated with bacteria l density, and Interferon-gamma and interleukin-12 expression with chronic inflammation score. Conclusions. The findings of this study indicate that, in children, Helicob acter pylori-induced inflammatory response would favour production of proin flammatory cytokines and development of cell-mediated immunity, namely Th1 response.