<i>L</i>. <i>monocytogenes</i> macrophage uptake and bacterial survival after Zn and atRA supplementation.

<p>J774 macrophage cells were infected with <i>L</i>. <i>monocytogenes</i> by centrifugation at 150 × g for 10 min at room temperature at a multiplicity of infection of 0.1. Bacterial uptake (A) was measured after 30 min of incubation at 37°C and bacterial survival (B) was measured after 24 h. ZnSO₄ (40 μM) or atRA (20 μM) were added 48 h before infection. Panel C shows fold increase of bacterial number in macrophages. Results are presented as fold increase of bacterial number relative to the number of phagocytosed bacteria. Data are the averages of triplicate samples from three identical experiments and error bars represent SD. Statistically significant differences, compared with the control, are indicated by asterisks.