FIG. 1.

Protective effect by therapeutic immunization with an H. pylori lysate preparation. Groups of mice were infected with H. pylori SS1 and either given CT alone at the time and again 1 week after the infection (hatched bar) or immunized four times with lysate plus CT after the establishment of infection (open bar). Infected untreated mice served as controls (filled bar). Results show geometric mean numbers (plus standard errors of the means) of bacteria cultured from the mouse stomach 6 weeks after start of infection. Mice immunized with lysate plus CT were protected significantly from a primary infection (P < 0.01). Results represent the composite of two consecutive experiments with eight mice per group, the results of which were so similar and overlapping that data were pooled for the graphic representation. The Mann-Whitney test was used for statistical analysis of differences between groups. ∗∗, P < 0.01 compared to the control group.