Figure 9.

Role of H. pylori NudA invasin in AGS cell entry determined using the gentamicin protection assay aided by TEM and anti-H. pylori antibody immunogold. H. pylori density is expressed as the percentage of total points intersections that were immunogold-positive (see Materials and Methods). Values are Means ± SEM. Left panel shows that the extracellular density of H. pylori WT and ΔnudA were not significantly different. In contrast, the middle and right panels show that the density of WT H. pylori attached to AGS cell membranes was significantly lower than that of the ΔnudA mutant (*p < 0.01) and the opposite relation for the density of intracellular H. pylori (*p < 0.01).