Moreover, accompanying the serious inflammatory changes as abscesses, erosions, leukocyte infiltration in the gastric mucosa and submucosa, accumulated leukocytes, including neutrophiles, microphages, and lymphocytes, were found for the first time in the gastric mucus in NZ-Δsp-napA group (1/11) and NZ-Δsp-napA+ltB (5/11) group. Here, NAPA is linked to abscess.