Studies on virus kinetics using infectious fluorescence-tagged hepatitis C virus cell culture.

ABSTRACT

AIM: Studies of the complete hepatitis C virus (HCV) life cycle have become possible with the development of a HCV-JFH1 cell culture system. METHODS: In this study, we constructed two fluorescence protein-tagged recombinant JFH1 virus clones, JFH1-EYFP and JFH1-AsRed, as well as two corresponding clones with adaptive mutations, JFH1-EYFP mutant and JFH1-AsRed mutant, that and were as effective as JFH1 in producing infectious virus particles, and investigated their viral infection life cycles. RESULTS: After infection of the fluorescence-tagged mutant viruses, infected cells increased exponentially. In cells, EYFP or AsRed and NS5A were expressed as a fusion protein and co-localized in core proteins. The rate of the cell-cell spread was dependent on the cell densities with a maximum of 10(2.5) /day. Treatment of cells with interferon or a protease inhibitor suppressed expansion of virus-positive cells. CONCLUSION: Taken together, these results indicate that fluorescence-tagged HCV is a useful tool to study virus infection life cycles and to assist in the search for novel antiviral compounds.