Fig. 1.

Distribution of H. pylori and H. felis in the mucus layer of mice and Mongolian gerbils. (A) The tissue surface of the H. pylori-infected gerbil depicted from the luminal side of the antrum. Several focus planes have been digitally combined, the H. pylori in the mucus layer subsequently highlighted in red. (B) The gastric mucosa and mucus of the H. felis-infected mouse and the H. pylori-infected gerbil are shown as schematic cross sections. The first 25 μm of the mucus layer on the tissue side (“juxtamucosal” mucus) are subdivided into 5-μm sections. The numbers represent the percentage of bacteria present within each section. The first 10 μm from the luminal surface is referred to as “luminal mucus,” the rest of the mucus layer as “central mucus.” H. felis was found located between 5 and 25 μm from the tissue surface (3). H. pylori, however, colonizes the whole section 0-25 μm from the tissue surface. Some H. pylori were attached to cells.