Immune Mechanisms of Viral Clearance and Disease Pathogenesis During Viral Hepatitis

Hepatocellular injury can occur in the context of a wide variety of diseases of variable etiology, including viral infections in which the immune response is believed to play a central role in viral clearance and disease pathogenesis. This chapter discusses the immune mechanisms thought to be operative in hepatitis B and C virus infections in light of important discoveries that have clarified hitherto obscure aspects of the immune response involved in termination of infection in those patients who successfully deal with these viruses. The possibility of stimulating innate immune responses in chronic hepatitis B virus (HBV) infection has been explored in the chimpanzee and woodchuck models of infection and in a phase II clinical trial in humans. Hepatitis C virus (HCV) can induce autophagy directly by using its proteins to recruit or interact with autophagy proteins. HBV and HCV are both equally able to induce chronic liver disease, although with different frequencies.