FIG. 6.
Neutralization of IL-17 inhibits induction of neutrophil chemoattractants and promotes Th1-associated responses in the stomachs of immunized mice after H. pylori challenge. Mice were either immunized sublingually with H. pylori lysate antigens and CT on four occasions (Ly + CT) or left unimmunized (UI) before challenge with an infectious dose of H. pylori bacteria. The mice were injected with a neutralizing monoclonal antibody against IL-17 or an IgG isotype control at days 5, 8, and 11 postchallenge and sacrificed at day 14. Gastric mRNA levels were analyzed by real-time PCR; the mean for the unimmunized control group treated with IgG isotype control antibody was set to 1 for each gene. The IFN-γ protein level was determined by cytometric bead array analysis of stomach saponin extracts. Pooled data from two independent experiments are shown as mean values for groups of 10 animals; error bars represent SEM. A significant difference in gene expression of immunized mice treated with anti-IL-17 or the isotype control, as assessed by Student's t test, is denoted by * (P < 0.05), ** (P < 0.01), or *** (P < 0.001).