Cell-based models of sustained, interferon-sensitive hepatitis C virus genotype 1 replication

J Virol Methods. 2006 Mar;132(1-2):195-203. doi: 10.1016/j.jviromet.2005.10.014. Epub 2005 Nov 28.

Abstract

We have previously reported hepatitis C virus (HCV) replication using a novel binary expression system in which mammalian cells were transfected with a T7 polymerase-driven full-length genotype 1a HCV cDNA plasmid (pT7-flHCV-Rz) and infected with vaccinia-T7 polymerase. We hypothesized that the use of replication-defective adenoviral vectors expressing T7 (Ad-T7pol) or cell lines stably transfected with T7 (Huh-T7) would alleviate cell toxicity and allow for more sustained HCV replication. CV-1, Huh7, and Huh-T7 cells were transfected with pT7-flHCV-Rz and treated with Ad-T7pol (CV-1 and Huh7 only). Protein and RNA were harvested from cells on days 1, 2, 3, 5, 7, and 9 post-infection. No cytotoxicity was observed at 9 days post-infection in any cell type. HCV positive- and negative-strand RNA expression were strongest during days 1-3 post-infection; however, HCV RNA remained detectable throughout the 9-day observation period. Furthermore, transfection with a replication-incompetent plasmid suggested that efficient HCV replication is dependent upon NS5B gene expression. Finally, after 1-2 days of IFN treatment, HCV positive-strand levels decreased significantly compared to HCV-infected but untreated samples (p<0.05). In conclusion, these refined binary systems offer more durable and authentic models for identification of host cellular processes critical to HCV replication and will permit longer-term analysis of virus-host interactions critical to HCV pathogenesis and the treatment of genotype 1 infections.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antiviral Agents / pharmacology
  • Blotting, Western
  • Cell Line
  • Enzyme-Linked Immunosorbent Assay
  • Hepacivirus / physiology*
  • Humans
  • Interferons / pharmacology*
  • RNA, Viral / biosynthesis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transfection
  • Viral Nonstructural Proteins / genetics
  • Viral Nonstructural Proteins / physiology
  • Viral Proteins / biosynthesis
  • Virus Replication* / drug effects

Substances

  • Antiviral Agents
  • RNA, Viral
  • Viral Nonstructural Proteins
  • Viral Proteins
  • Interferons
  • NS-5 protein, hepatitis C virus