Transfer of antigen-pulsed dendritic cells induces specific T-Cell proliferation and a therapeutic effect against long-term Helicobacter pylori infection in mice.

Helicobacter pylori causes persistent infection of the stomach and results in chronic gastritis and peptic ulcers. Jaws II cells, derived from mouse bone marrow, were pulsed with live or formalin-killed or whole-cell sonicates (WCS) of H. pylori. Representative cell surface molecules were expressed at substantial levels on Jaws II cells, indicating that appropriate maturation of the cells was achieved with the three H. pylori antigens without any significant differences. H. pylori WCS-pulsed Jaws II cells secreted a significant amount of tumor necrosis factor alpha into the culture supernatant. The naïve T cells exposed to the WCS-pulsed Jaws II cells showed significant proliferation and gamma interferon (IFN-gamma) and interleukin-10 (IL-10) production in vitro. A 2-log reduction in the number of colonizing bacteria was observed in the mice treated with the WCS-pulsed Jaws II cells; however, no significant reductions were achieved in mice treated with Jaws II cells pulsed with other H. pylori antigens. Up-regulated production of IFN-gamma and IL-10 was observed in the stomachs of the mice treated with the WCS-pulsed Jaws II cells, which is consistent with the result obtained in vitro. There were no differences in gastritis scores or H. pylori-specific antibody titers among the mice treated with Jaws II cells pulsed with the three different H. pylori antigens. The results suggest that Th1 cell-mediated immunity in combination with Th2 cell-mediated immunity plays a role in reducing colonizing bacterial numbers in mice with chronic H. pylori infections.