title: In vitro resistance to interferon-alpha of hepatitis B virus with basic core promoter double mutation.
abstract: The hepatitis B virus (HBV) genome basic core promoter (BCP) modulates HBeAg secretion at the transcriptional level. In addition to pre-core mutations, variations in the BCP are related to hepatitis B e antigen (HBeAg)-negative chronic hepatitis B. HBeAg-negative chronic hepatitis B patients show a lower sustained response to interferon (IFN). The aim of this study was to determine if there is a relationship between HBV BCP mutation and sensitivity of HBV to IFN-alpha in vitro. BCP mutations were introduced by site-directed mutagenesis and the entire genomes of wild-type and mutant HBV were transiently transferred into Huh7 cells by calcium phosphate transfection. With or without IFN-alpha, viral products in the culture medium and viral replication intermediates in the cytoplasm were detected 3 days after transfection. The amount of hepatitis B surface antigen (HBsAg) secreted by wild-type HBV and the BCP mutant was similar, while HBeAg secreted by the mutant was decreased by 35.4%. HBV particles and replication intermediates of the BCP mutant were increased. After IFN-alpha was added, HBeAg, HBV DNA and HBV replication intermediates decreased for both the wild-type HBV (by 25.7%, 31.8%, 29.8%, respectively) and the BCP mutant (by 8.4%, 27.4%, 10.1%, respectively). These data indicate that HBV harboring the BCP double mutation has stronger replication competence and lower sensitivity to IFN-alpha than wild-type.
authors.affiliation: Hepatology Institute, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Lai
authors.initials: L
authors.lastname: Wei
authors.forename: Dong
authors.initials: D
authors.lastname: Jiang
authors.forename: Xu
authors.initials: X
authors.lastname: Cong
authors.forename: Ran
authors.initials: R
authors.lastname: Fei
authors.forename: Hongsong
authors.initials: H
authors.lastname: Chen
authors.forename: Jiang
authors.initials: J
authors.lastname: Xiao
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D024882:Drug Resistance, Viral / Q000235:genetics; D016679:Genome, Viral / Q000235:genetics; D006514:Hepatitis B Surface Antigens / Q000378:metabolism; D006513:Hepatitis B e Antigens / Q000378:metabolism; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology*; D016297:Mutagenesis, Site-Directed; D010957:Plasmids / Q000235:genetics; D017354:Point Mutation; D011401:Promoter Regions, Genetic / Q000235:genetics*; D014162:Transfection; D014758:Viral Core Proteins / Q000235:genetics*; D014779:Virus Replication / Q000187:drug effects / Q000235:genetics
chemical_list: D000998:Antiviral Agents; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D016898:Interferon-alpha; D014758:Viral Core Proteins