Fig. 3. HCV particles of higher density exhibit faster infection initiation kinetics.

Huh7 cells were plated in 96-well plates, infected with ~ 100 FFU of 1.01 g/ml (open circles) or 1.09 g/ml (grey diamonds) density fractions of HCVcc^wt in 1% cDMEM. At indicated time points p.i., inoculum was removed from triplicate wells, cells were washed twice with 1X PBS and overlaid with 10% cDMEM containing 0.25% methylcellulose. Forty-eight hours p.i., HCV foci were visualized by HRP-based immunocytochemistry staining using an anti-NS5A antibody, quantified and are expressed as mean number (no.) of foci detected/well ± stdev for triplicate samples. Time course of infection initiation is shown over (A) 36 hours (Additionally, the average number of foci obtained after maximal foci formation was observed (23–36 h p.i.) is shown.) and (B) 12 hours.