Effects of chronic Helicobacter pylori infection on the serum inflammatory cytokines in Mongolian gerbils at different time points. The serum levels of cytokines including IL-1β, IL-2, IL-12, IL-4, IL-10, IFN-γ, and TNF-α were measured by ELISA at 6 and 12 mo after Helicobacter pylori (H. pylori) infection. Data are presented as mean ± SEM from eight to ten mice per group. Cytokines were not significant different except IL-4 (aP < 0.05 between H. pylori infected mice and their controls). IL: Interleukin; TNF: Tumor necrosis factor; IFN: Interferon.