Impact of I233V mutation in the hepatitis B virus reverse transcriptase domain on adefovir resistance / 中华传染病杂志

ABSTRACT

Objective To construct an in vitro phenotypic analysis technology for evaluating the impact of I233V mutation in the hepatitis B virus(HBV)reverse transcriptase(rt)domain on adefovir (ADV)resistance.Methods A site-directed mutagenesis was used to construct recombinant HBV plasmid containing rtI233V,rtA181V and rtN236T.The culture solution with varied concentration ADV was added after the transient transfection of hepatocyte-derived cell lines with recombinant wild type and mutant HBV clones.Three days later,the cells were harvested and the replicable intermediate was detected by the Southern blot assay.The half maximal inhibitory concentration (IC50) and folds of resistance were calculated by the Table Curve2D software according to the Southern blot results.Results The variant harboring rtI233V mutation exhibited a 6.5-fold decrease of susceptibility to ADV with IC50 of(1.69±0.52)/μmol/L compared to the wild type HBV.Conclusion The findings suggest that the emergence of a single substitution at position rtI233V is sufficient to induce resistance to ADV.