FIG. 1.

CSFV-mediated cell survival after poly(IC) treatment is strain independent. Cell survival of SK-6 cells infected with three CSFV strains of different virulence was monitored by crystal violet staining 48 h after poly(IC) treatment. (A) The percentage of cell survival was calculated from the ratio of the OD₅₉₅ of each poly(IC)-treated well to the average OD₅₉₅ of the corresponding eight untreated wells (see Materials and Methods). The mean values with standard deviation from three independent experiments in SK-6 cells infected with CSFV strains vEy-37 (⋄), vA187-1 (□), and vRiems (○) or mock- infected cells (▵) are shown for decreasing poly(IC) concentrations. (B) Seventy-two hours p.i., at the time of poly(IC) addition, parallel cultures were analyzed for expression of the viral glycoprotein E2 by using immunoperoxidase staining.