Hepatitis C virus: propagation, quantification, and storage.

Area of Science:

• Virology
• Hepatology
• Molecular Biology

Background:

• Hepatitis C virus (HCV) causes chronic liver diseases like cirrhosis and cancer.
• HCV has limited animal tropism, hindering traditional research methods.
• In vitro propagation of natural HCV isolates is challenging.

Purpose of the Study:

• To describe a protocol for rescuing infectious HCV from cDNA clones.
• To establish methods for propagating and titrating two distinct HCV genotypes (1a and 2a).
• To facilitate in vitro studies of HCV replication and pathogenesis.

Main Methods:

• Transfection of viral RNA from cDNA clones (genotype 1a pH77S, 2a pJFH-1) into permissive cells.
• Development of specific propagation methods tailored to each viral clone's behavior.
• Focus-forming unit (FFU) assay for infectious virus titration via immunostaining.

Main Results:

• Successful rescue of infectious HCV from transfected RNA clones.
• Demonstrated differential propagation efficiencies between genotype 1a and 2a clones.
• Established a reliable FFU assay for quantifying infectious viral particles.

Conclusions:

• The described protocol enables the generation of infectious HCV in vitro.
• This system provides a valuable tool for studying HCV biology and evaluating antiviral therapies.
• The methods facilitate research into chronic liver disease pathogenesis caused by HCV.