The Molecular Components of Hepatitis B Virus

Abstract

The search for new antigenic polymorphisms among different human populations, undertaken by B. S. Blumberg and colleagues in the early 1960’s, resulted in the discovery of a substance in the sera of an Australian aborigine which reacted in immunodiffusion analysis with a component in the serum of a hemophilia patient in the United States (1–3). The finding of this “Australia antigen” (Au) in the sera of leukemia prone Down’s syndrome patients, and the seroconversion of one patient from Au^- to Au⁺ associated with raised serum transaminase levels, suggested liver involvement, and first established a link between Au and acute viral hepatitis (4), Further work confirmed these findings (5–8) and revealed that Au is, or Is part of, a transmissible agent capable of establishing evidence of infection (serum Au or anti-Au) in drug addicts (9, 10) and in patients undergoing hemodialysis (11, 12) or otherwise exposed parenterally to blood or blood fractions (5, 13–16). The subsequent screening for Au⁺, or hepatitis B virus surface antigen (HBsAg) positive sera, dramatically reduced the incidence of post-transfusion hepatitis (3, 17) and paved the way for both isolation and characterization of HBsAg as well as future vaccine development.