(A–C) Primary keratinocytes, MEFs, and neurons were pre-treated for 18 hours with the indicated amount of IFN-β. Following pre-treatment, all cells were infected with 0.5 MOI of HSV1-GFP. At the time points indicated, cells were isolated and analyzed for GFP expression by flow cytometry. Data are shown as number of infected cells (GFP+) per 10,000 cell events for MEFs (A), keratinocytes (B), and neurons (C). Data are representative of four independent experiments. See also Figure S2.