FIG. 6.

Cytotoxic and cytostatic effects of drug combinations on HepG2 49-29 cells. HepG2 49-29 cells were seeded into 96-well plates at a density of 2 × 10⁴ cells/well and exposed to the indicated compounds for 1 week. Cell viability was subsequently assayed by XTT cleavage. Three independent assays were performed in triplicate with each drug tested alone and in combination with adefovir at the highest doses used for the antivirus assays (1.5 μM adefovir, 0.12 μM lamivudine, 0.009 μM entecavir, 2.04 μM L-dT, 0.24 μM FTC, and 1.5 μM tenofovir). The mean number of viable cells for each treatment condition (as a percentage of the untreated controls) is shown; error bars indicate standard deviations. No significant cytotoxicity was observed for any of the cultures treated with one or two drugs (P = 0.67; one-way ANOVA).