Conditional Inducible Triple-Transgenic Mouse Model for Rapid Real-Time Detection of HCV NS3/4A Protease Activity

PLoS One. 2016 Mar 4;11(3):e0150894. doi: 10.1371/journal.pone.0150894. eCollection 2016.

Abstract

Hepatitis C virus (HCV) frequently establishes persistent infections that can develop into severe liver disease. The HCV NS3/4A serine protease is not only essential for viral replication but also cleaves multiple cellular targets that block downstream interferon activation. Therefore, NS3/4A is an ideal target for the development of anti-HCV drugs and inhibitors. In the current study, we generated a novel NS3/4A/Lap/LC-1 triple-transgenic mouse model that can be used to evaluate and screen NS3/4A protease inhibitors. The NS3/4A protease could be conditionally inducibly expressed in the livers of the triple-transgenic mice using a dual Tet-On and Cre/loxP system. In this system, doxycycline (Dox) induction resulted in the secretion of Gaussia luciferase (Gluc) into the blood, and this secretion was dependent on NS3/4A protease-mediated cleavage at the 4B5A junction. Accordingly, NS3/4A protease activity could be quickly assessed in real time simply by monitoring Gluc activity in plasma. The results from such monitoring showed a 70-fold increase in Gluc activity levels in plasma samples collected from the triple-transgenic mice after Dox induction. Additionally, this enhanced plasma Gluc activity was well correlated with the induction of NS3/4A protease expression in the liver. Following oral administration of the commercial NS3/4A-specific inhibitors telaprevir and boceprevir, plasma Gluc activity was reduced by 50% and 65%, respectively. Overall, our novel transgenic mouse model offers a rapid real-time method to evaluate and screen potential NS3/4A protease inhibitors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Computer Systems*
  • Disease Models, Animal
  • Hepacivirus / enzymology*
  • Liver / drug effects
  • Liver / metabolism
  • Liver / pathology
  • Liver / virology
  • Luciferases / metabolism
  • Mice, Transgenic
  • Oligopeptides / pharmacology
  • Plasmids / metabolism
  • Proline / analogs & derivatives
  • Proline / pharmacology
  • Protease Inhibitors / pharmacology
  • Reproducibility of Results
  • Viral Nonstructural Proteins / metabolism*

Substances

  • NS3 protein, hepatitis C virus
  • Oligopeptides
  • Protease Inhibitors
  • Viral Nonstructural Proteins
  • telaprevir
  • N-(3-amino-1-(cyclobutylmethyl)-2,3-dioxopropyl)-3-(2-((((1,1-dimethylethyl)amino)carbonyl)amino)-3,3-dimethyl-1-oxobutyl)-6,6-dimethyl-3-azabicyclo(3.1.0)hexan-2-carboxamide
  • Proline
  • Luciferases

Grants and funding

This work was supported by the National Natural Science Foundation of China (No.30872218, 81171637); the National High Technology Research and Development Program (2007AA02Z154); http://www.nsfc.gov.cn/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.