Figure 2. In vivo colonization under simulated prandial gastric conditions.

The three panels show the luminal pH profiles (red bullets) that were titrated to simulate the prandial phase in breast-fed babies (left), young children (middle), and adults (right). The H. pylori inoculum is given during the simulation of the meal, as administration at the beginning of the profile would lead to rapid loss of bacterial motility due to the acidic fasting pH in profiles A and C. In profile B, the pH is remaining at 4 between the meals. The time points when an inoculum of 10⁸ motile H. pylori was added in the in vivo experiments in the Mongolian gerbil are marked by green arrows.