Mechanistic Characterization and Molecular Modeling of Hepatitis B Virus Polymerase Resistance to Entecavir
Figure 5
Analysis of ETVr through strand-specific DNA synthesis in culture.
Cell culture ETV EC50 determinations were made for wildtype and various resistant HBVs. The levels of HBV DNA synthesized in the presence of ETV was determined by HBV-specific probe hybridization to HBV nucleocapsid DNA from the cultures. The probes used were the typical double-stranded DNA probe, or strand-specific riboprobes which hybridized to a single HBV DNA strand. Comparison of strand-specific EC50 versus double stranded EC50 for wildtype polymerase (WT) or LVDr M204V+L180M HBV, or the LVDr substitutions with ETVr substitutions (+T184, +S202, +M250) as indicated. Values at 4000 nM indicate that 50% inhibition was not observed at the highest ETV concentration tested.