FIG. 6.

Cytochalasin D inhibits invasion of endothelial cells by L. monocytogenes. HUVEC were cultured with increasing amounts of cytochalasin D for 60 min and then were infected with 10⁴ L. monocytogenes EGD organisms. Cells and bacteria were incubated for 60 min and washed, and then one set of triplicate wells were lysed and bound CFU were quantified by serial dilution and plating. The remaining cells were incubated with medium containing gentamicin for 60 min, and then intracellular bacterial CFU were quantified as before. Percent bacterial binding (open bars) was calculated as follows: CFU bound/CFU added. Percent invasion (hatched bars) was calculated as follows: intracellular bacterial CFU/CFU bound. Results presented are the mean (±SEM) percent control (no cytochalasin D added) binding and invasion from three experiments.