Minicircle HBV cccDNA with a Gaussia luciferase reporter for investigating HBV cccDNA biology and developing cccDNA-targeting drugs

Sci Rep. 2016 Nov 7:6:36483. doi: 10.1038/srep36483.

Abstract

Chronic Hepatitis B Virus (HBV) infection is generally not curable with current anti-viral drugs. Virus rebounds after stopping treatment from the stable HBV covalently-closed-circular DNA (cccDNA). The development of drugs that directly target cccDNA is hampered by the lack of robust HBV cccDNA models. We report here a novel HBV cccDNA technology that will meet the need. We engineered a minicircle HBV cccDNA with a Gaussia Luciferase reporter (mcHBV-GLuc cccDNA), which serves as a surrogate to measure cccDNA activity. The mcHBV-GLuc cccDNA was easily produced in bacteria, and it formed minichromosomes as HBV cccDNA episome DNA does when it was transfected into human hepatocytes. Compared to non-HBV minicircle plasmids, mcHBV-GLuc cccDNA showed persistent HBV-GLuc activity and HBx-dependent gene expression. Importantly, the mcHBV-GLuc cccDNA showed resistance to interferons (IFN) treatment, indicating its unique similarity to HBV cccDNA that is usually resistant to long-term IFN treatment in chronic HBV patients. Most importantly, GLuc illuminates cccDNA as a surrogate of cccDNA activity, providing a very sensitive and quick method to detect trace amount of cccDNA. The mcHBV-GLuc cccDNA model is independent of HBV infection, and will be valuable for investigating HBV cccDNA biology and for developing cccDNA-targeting drugs.

Publication types

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

MeSH terms

  • Antiviral Agents / chemistry
  • Antiviral Agents / metabolism*
  • Antiviral Agents / pharmacology
  • Cell Line
  • Chromatin Immunoprecipitation
  • DNA, Circular / chemistry
  • DNA, Circular / metabolism*
  • DNA, Viral / analysis
  • DNA, Viral / metabolism*
  • Genes, Reporter
  • Hep G2 Cells
  • Hepatitis B virus / genetics*
  • Humans
  • Interferons / chemistry
  • Interferons / metabolism
  • Interferons / pharmacology
  • Luciferases / genetics
  • Luciferases / metabolism
  • Microscopy, Fluorescence
  • Plasmids / genetics
  • Plasmids / metabolism
  • Transcriptome / drug effects

Substances

  • Antiviral Agents
  • DNA, Circular
  • DNA, Viral
  • Interferons
  • Luciferases