Real-time imaging of hepatitis C virus infection using a fluorescent cell-based reporter system

Hepatitis C virus (HCV), which infects 2-3% of the world population, is a causative agent of chronic hepatitis and the leading indication for liver transplantation1. The ability to propagate HCV in cell culture (HCVcc) is a relatively recent breakthrough, and a key tool in the quest for specific antiviral therapeutics. Monitoring HCV infection in culture generally involves bulk population assays and/or terminal processing of potentially precious samples. Live-cell imaging avoids this, but necessitates genetically modified reporter viruses, which often exhibit profound replication defects. Here we develop a cell-based fluorescent reporter system that allows sensitive distinction of individual HCV-infected cells in live or fixed samples. We demonstrate use of this technology for several previously intractable applications, including live-cell imaging of viral propagation and host response, as well as visualizing infection of primary hepatocyte cultures. Integration of this reporter with modern image-based analysis methods could open new doors for HCV research.