Fig 3.

The downregulation of Rho GTPases impairs ASFV infection. Vero cells incubated for a range of times with increasing concentrations of toxin B from Clostridium difficile (CdTB) were infected with ASFV at 0.5 PFU/cell. (A) As described in the text, virus titers from infected cells at 24 hpi were determined by plaque assay and are shown as a percentage of untreated infected cells. (B) The number of infected cells at 3 hpi is represented as a percentage of untreated infected cells. The means and SD correspond to three independent experiments. Values that are significantly different from each other are indicated (**, P < 0.01; *, P < 0.05). (C) The expression of early (p30) and late (p72) viral proteins was analyzed at several time points during infection in cells treated with 100 ng of CdTB/ml 2 h prior to infection or 3 hpi and compared to untreated infected cells. β-Actin was used as a protein load control. (D) Vero cells were infected with B54GFP-2 in the presence or absence of CdTB and examined by confocal microscopy at 16 hpi. Viral factories from 16 to 20 cells were measured, and maximum dimensions are represented as means with the corresponding SD. A representative image is shown, where viral factories were detected by direct visualization of p54-EGFP (green). Nuclei (blue) and actin (red) were detected by Hoechst staining and anti-β actin antibody, respectively. Bar, 10 μm. Values significantly (P < 0.01) different from controls are indicated (**).