Hepatitis C viral proteins affect cell viability and membrane permeability

Area of Science:

• Hepatology
• Virology
• Molecular Biology

Background:

• Hepatitis C virus (HCV) infection is a major cause of chronic liver disease.
• The specific mechanisms by which HCV proteins impact host cell viability are not fully understood.

Purpose of the Study:

• To investigate the effects of expressing all structural and nonstructural hepatitis C virus proteins on the viability of hepatic cells.
• To elucidate the role of HCV protein expression in inducing cell death pathways.

Main Methods:

• Huh-7 cells were transfected with a full-length HCV cDNA clone for protein expression.
• HCV protein expression was facilitated by a replication-defective adenovirus encoding T7 RNA polymerase.
• Cell viability was assessed using trypan blue assay, flow cytometry, cell cycle analysis, TUNEL assay, and microscopy.

Main Results:

• Expression of full-length HCV proteins significantly reduced cell viability.
• Cells expressing HCV proteins exhibited loss of membrane permeability and apoptotic cell death.
• Apoptosis was confirmed by sub-G0 cell cycle peak, DNA fragmentation, and nuclear condensation.

Conclusions:

• Expression of all structural and nonstructural HCV proteins in hepatic cells induces apoptotic cell death.
• This induction of apoptosis is a significant event potentially contributing to the pathogenesis of chronic hepatitis C infection in humans.