B cells pulsed with Helicobacter pylori antigen efficiently activate memory CD8+ T cells from H. pylori-infected individuals

• Helicobacter pylori infection causes chronic gastritis that may progress to peptic ulcers or gastric adenocarcinoma and thereby cause major world-wide health problems. Previous studies have shown that CD4+ T cells are important in the immune response to H. pylori in humans, but the role of CD8+ T cells is less clear. In order to study the CD8+ T cell response to H. pylori in greater detail, we have evaluated efficient conditions for activation of CD8+ T cells in vitro. We show that H. pylori-reactive CD8+ T cells can be activated most efficiently by B cells or dendritic cells pulsed with H. pylori antigens. We further show that the majority of CD8+ T cells in H. pylori-infected gastric mucosa are memory cells, and that memory CD8+ T cells sorted from peripheral blood of H. pylori-infected individuals respond 15-fold more to H. pylori urease compared to memory cells from uninfected subjects. We conclude that CD8+ T cells do participate in the immune response to H. pylori, and this may have implications for the development of more severe disease outcomes in H. pylori-infected subjects.

Keyword

Adult

Antigens

Bacterial/immunology/*physiology

B-Lymphocyte Subsets/*immunology/*microbiology

CD8-Positive T-Lymphocytes/*immunology

Cell Proliferation

Cells

Cultured

Gastric Mucosa/immunology/microbiology

Helicobacter Infections/*immunology

Helicobacter pylori/*immunology

Humans

*Immunologic Memory

Middle Aged

Monocytes/immunology

Publication and Content Type

ref (subject category)

art (subject category)