Figure 6.

Effect of cytochalasin D (CD) treatment on VacA-induced vacuolation of HEp-2 cells. Neutral red uptake was measured either 1) in cells previously exposed to VacA⁺ BCF pulse, or in control cells and then treated with CD dissolved in DMSO or with DMSO alone (VacA preloaded); or 2) in cells treated with CD dissolved in DMSO, or with DMSO alone and then exposed or not (Control) to VacA⁺ BCF pulse (VacA afterloaded) (see Methods). Incubation for vacuole development: 5 h at 37°C in HBSS containing 5 mM NH₄Cl. Means = SEM of three independent experiments. * = p < 0.05 versus paired Control. ° = p < 0.05 versus the same condition but DMSO-treated.