Innate antiviral immune responses to hepatitis B virus.

Hepatitis B virus (HBV) is a major cause of acute and chronic hepatitis in humans. As HBV itself is currently viewed as a non-cytopathic virus, the liver pathology associated with hepatitis B is mainly thought to be due to immune responses directed against HBV antigens. The outcome of HBV infection is the result of complex interactions between replicating HBV and the immune system. While the role of the adaptive immune response in the resolution of HBV infection is well understood, the contribution of innate immune mechanisms remains to be clearly defined. The innate immune system represents the first line of defense against viral infection, but its role has been difficult to analyze in humans due to late diagnosis of HBV infection. In this review, we discuss recent advances in the field of innate immunity to HBV infection.