<i>Salmonella</i> are killed by THP1 cells and primary human macrophage cells.

<p>(A) Intracellular <i>Salmonella</i> in THP-1 cells differentiated for 3 days in the presence of 20 ng/mL PMA (open circles) or primary human monocyte derived macrophages (MDMs, closed circles) differentiated for 7 days in the presence of 100 ng/mL MCSF. Growth normalized to 1 h pi. Data are means ± SD from three independent experiments. (B) Cytokine expression as measured by ELISA for TNF-α, IL-8, and IL-12p40 in THP-1 cells (white bar) and human macrophages (black bars) in uninfected and <i>Salmonella</i>-infected cells at 6 and 24 h pi. Representative plots from three independent experiments. Statistical significance was determined as compared to the uninfected control for each strain using an unpaired <i>t</i>-test. (C) Representative maximum intensity projection images of <i>Salmonella</i> (red) infected MDMs and THP-1 cells differentiated in the presence of either 200 ng/mL PMA (2 day and 5 day) or 20 ng/mL PMA (3 day) at 1 h pi and stained for LAMP1 (green). Scale bars are 15μm and 5uM (insert). (D) Quantification of LAMP1 positive <i>Salmonella</i> in MDMs (red circles) and THP1 cells differentiated for 2 days (open circles), 3 days (grey squares), and 5 days (closed circles). Data are means ± SD from three independent experiments.