The immune response against pre-S2-encoded peptides and human serum albumin during hepatitis B virus infection.

Serum antibodies to human serum albumin (HSA) and its receptor structures (pre-S2) on HBV/HBsAg particles of IgG class were measured in patients with naturally acquired immunity to hepatitis B, HBsAg carriers with chronic liver disease, 'healthy' symptomless HBsAg carriers and controls. ELISA systems in which serum samples were diluted in 0.05 M PBS to give low protein concentrations followed by incubation at 4 degrees C were used. Anti-HSA and anti-pre-S2 were produced in patients during the acute phase of hepatitis B infection but were short-lived. The antibodies were absent in 'healthy' symptomless HBsAg carriers but present in the majority of HBsAg carriers with major liver disease. These results indicate that humoral immune responses of IgG class, normally initiated during the acute phase of HBV infection against the host 'self'-component HSA and/or its receptor structures, are down-regulated by immunological mechanisms while continuous production of these antibodies is associated with the pathogenesis of chronic HBV-induced liver disease.