Fluorescence microscopy and image analysis of bacterial pathogen spread from cell to cell.

<p>Mock- and ARPC4-treated cells were infected with GFP-expressing wild type (<i>10403S</i>) or mutant (<i>10403SΔactA</i>) <i>L. monocytogenes</i> for 10 hrs. Left panel, Nuclei; middle panel, Bacteria and right panel, Image analysis. Computer-assisted image analysis was used to determine the number of nuclei corresponding to uninfected and infected cells (red and green objects, respectively).