Figure 3.

Experimental design of the gentamicin protection assay. AGS cells were prepared to grow to monolayer in 8 wells in a 12-well plate (four wells for WT strain J99 and four wells for ΔnudA mutant. Each strain was inoculated into the four AGS cell types. Two wells (on the left) were designed as negative control of gentamicin treatment as it was added to H. pylori suspension when inoculated to the cells, and then treated with or without saponin after 12 h inoculation. A third well was used for measurement of H. pylori bound to cell membranes in the conditions without gentamicin and saponin. The last well was designed for measurement of H. pylori invasion into the cell with gentamicin and saponin added. The chamber slides prepared for morphologic observation were exactly the same as above.