The immune response to hepatitis B virus.

Cell-mediated immune response to nucleocapsid determinants, including HBcAg and HBeAg, are important in the clearance of HBV-infected hepatocytes. This process is modulated by interferon and humoral responses to these antigens. Antibodies to the envelope proteins contribute to protective immunity, but the relative importance of pre-S and S determinants in evoking a response and the relative contributions of these antibodies in virus neutralization remains unclear. It is known, however, that antibodies binding to the RFHBs1 epitope on the HBs sequence 124-137 are capable of protecting against further infection and are present in convalescent subjects and in recipients of the plasma-derived and recombinant hepatitis B vaccines. Detailed analysis of the specificity of the anti-HBs response in vaccinees shows it to be qualitatively similar to that seen during recovery from natural infection.