Effects of rebamipide on production of several cytokines by human peripheral blood mononuclear cells.

Recently, the relative contributions of local T helper cell responses of the Th1-type and Th2-type to the pathogenesis of gastritis and peptic ulcers associated with Helicobacter pylori infection have been examined. However, the results were controversial with respect to whether cellular immunity (Th1-type) or humoral immunity (Th2-type) responses predominate in H. pylori infection and with respect to how these responses may contribute to disease pathogenesis. In this study, we investigated the characteristics of the production of various cytokines induced by H. pylori or lipopolysaccharide (LPS), which was derived from H. pylori or Escherichia coli, in human peripheral blood mononuclear cells (PBMC). Live H. pylori induced production of many cytokines, such as IL-1beta, IL-10, IL-8, IFN-gamma, and TNF-alpha, whereas we could not detect IL-2 or IL-4. Moreover, we evaluated the effect of rebamipide on the production of several cytokines from PBMC induced by various stimuli. Rebamipide suppressed the production of IL-8, IL-10, TNF-alpha, and IL-1beta induced by H. pylori in a dose-dependent manner. On the other hand, the production of IL-12 induced by H. pylori showed a tendency to increase as a result of treatment of the cells with rebamipide. These results suggested that rebamipide might be effective in regulating cytokine responses in the H. pylori-infected host and maintaining host immunity. Moreover, it might contribute positively to disease progression and bacterial eradication.