Figure 4.

IRF5 enhances cell death in HCV replicon cells. A, cell viability as determined by the MTS assay is shown for Huh7.5, MH-14, and C-5B cells. Cells were transiently transfected with the indicated concentrations of FLAG-IRF5 plasmid and harvested 24 h later. Data are means ± S.D. (error bars) of six independent replicates. B, representative fluorescent images of AO and EtBr co-staining in MH-14 and C-5B cells transfected with 0.1 μg of empty vector (V) or FLAG-IRF5 plasmid (IRF5). Images were taken at ×20 magnification. C, summary of data from B showing the percentage of EtBr-positive (apoptotic) cells 12 and 24 h post-transfection. White bars, cells transfected with empty vector; black bars, cells transfected with FLAG-IRF5 plasmid. D, representative dot plots from flow cytometry analysis of C-5B cells left untransfected or transiently transfected with 80 ng of empty vector (V) or FLAG-IRF5 (IRF5) plasmid. Apoptosis was determined from Annexin V-FITC single-stained cells 12 h later. E, summary of data from D showing mean percentage of single-stained cells ± S.D. Plotted data are duplicate data points from three independent replicates. F, same as E except data are from Huh7.5 cells. *, p < 0.05; ***, p < 0.0001.