Fig. 1

Virulence potential of 20 L. monocytogenes ST155 strains in human intestinal epithelial Caco2 cells. Invasion efficiency (%, a) and intracellular growth coefficient (IGC, b) are shown as mean value ± SD of three biological replicates determined in duplicates. * statistically significant differences compared to the ScottA variant (p < 0.05)