HBV subgenotypes F1b and F4 replication induces an incomplete autophagic process in hepatocytes: Role of BCP and preCore mutations

PLoS One. 2018 May 8;13(5):e0197109. doi: 10.1371/journal.pone.0197109. eCollection 2018.

Abstract

Hepatitis B virus (HBV) genotypes and mutants have been associated with differences in clinical and virological characteristics. Autophagy is a cellular process that degrades long-lived proteins and damaged organelles. Viruses have evolved mechanisms to alter this process to survive in host cells. In this work, we studied the modulation of autophagy by the replication of HBV subgenotypes F1b and F4, and the naturally occurring mutants BCP and preCore. HBV subgenotypes F1b and F4 replication induced accumulation of autophagosomes in hepatoma cells. However, no autophagic protein degradation was observed, indicating a blockage of autophagic flux at later stages. This inhibition of autophagy flux might be due to an impairment of lysosomal acidification in hepatoma cells. Moreover, HBV-mediated autophagy modulation was independent of the viral subgenotypes and enhanced in viruses with BCP and preCore naturally occurring mutations. These results contribute to understand the mechanisms by which different HBV variants contribute to the pathogenesis of HBV infections. In addition, this study is the first to describe the role that two highly prevalent naturally occurring mutations exert on the modulation of HBV-induced autophagy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autophagy / genetics*
  • DNA, Viral / genetics
  • Genotype*
  • Hepatitis B virus / genetics*
  • Hepatitis B virus / pathogenicity
  • Hepatocytes / virology
  • Humans
  • Lysosomes / genetics
  • Lysosomes / virology
  • Mutation
  • Promoter Regions, Genetic / genetics
  • Proteolysis
  • Virus Replication / genetics

Substances

  • DNA, Viral

Grants and funding

This work was supported by grants from: Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) [PIP1122015010095CO]; Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT) [PICT2014-1672] and UBACyT [20020130100505BA 2014-2017] to RHC. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.