Figure 3. Intracellular survival and replication of P. aeruginosa PAO1 and its type III secretion mutants in corneal epithelial cells in the presence bafilomycin A1 (200 nM) (black boxes) versus control cells treated with vehicle only (grey boxes).

Bafilomycin treatment restored intracellular survival of the exsA mutant to that of the popB mutant and wild-type PAO1. Bafilomycin A1 was added 1 h before infection and continued throughout the assay. Intracellular survival was expressed as the mean percentage increase in viable intracellular bacteria at 8 h versus 4 h post-infection (+/- SEM). A representative experiment of 3 independent experiments in shown above. ANOVA (p = 0.0002) and Welch’s corrected t-test were used for statistical analysis (* p < 0.05).