FIG. 4.

Infectious HBV particle production and IFN-mediated induction of antiviral cytidine deaminases in HepG2-H1.3 cells. (A) Secretion of HBV virions from HBV-producing hepatoma cell lines. HBV was concentrated from cell culture medium of HepG2.2.15 and HepG2-H1.3, and obtained virus stocks were sedimented through a CsCl step gradient (1.2 to 1.4 g/ml). The different gradient fractions from bottom to top were analyzed by dot blot analysis using a ³²P-labeled HBV DNA probe. (B) A3G and, to a small extent, A3F and A3B are induced in HepG2-H1.3 cells upon IFN-γ treatment. Levels of A3G, A3F, and A3B gene expression were assessed by quantitative real-time RT-PCR 24 h after treatment with the indicated cytokines. Quantities were normalized using TBP and TFRC and expressed as change (n-fold) relative to the baseline levels obtained from untreated HepG2-H1.3 cells. Values represent means ± standard deviations for independent duplicates.