FIG. 6.

Effect of IFN-γ on the accumulation of cccDNA and replicative intermediates in primary duck hepatocytes infected with DHBV. Primary duck hepatocytes were cultured in the presence of specified concentrations of recombinant DuIFN-γ. IFN was first added either 1 day prior to infection (d−1), on the day of infection (d0), or 1 or 2 days thereafter (d1 and d2, respectively). cccDNA and replicative intermediates were isolated from IFN-treated cells 4 days postinfection (p.i.). Untreated cultures were harvested on the day indicated. Sample loaded is equivalent to one-fifth of a 60-mm-diameter plate. Replicative intermediates are shown on the upper panel, and cccDNA is shown on the lower panel. Gel migration positions of relaxed circular (rc), single-stranded (ss), and covalently closed circular (ccc) forms of viral DNA are indicated.