FIG. 2.

Effect of TNF-α on HBV replication and cell viability. HepG2 cells were transfected with HBV 1.2-mer genomic DNA and treated with TNF-α for 4 days, with daily replenishment at the indicated doses. (A) Cytoplasmic core particles were purified from equal numbers of cells, and associated HBV DNA was extracted and detected by Southern blot analysis. Poly(A)⁺ mRNA was selected and detected by Northern blot analysis from duplicate plates of cells. RC, relaxed circular; DL, double stranded linear; SS, single stranded linear. (B) HepG2 cells were transfected with the vector alone or with wild-type HBV genomic DNA, with or without treatment with 5 ng of TNF-α per ml. At 4 days posttransfection, cells were assayed for percent death by the LDH assay. Untransfected cells were treated with 5 ng of TNF-α per ml and 10 μg of cycloheximide (Cyclo.) per ml for 10 h and then assayed for cell death. Results of both experiments were averaged from three independent assays and quantified by densitometry. Data were normalized to the untreated sample.