IGG SUBCLASS ANALYSIS OF ANTI-HBS ANTIBODIES PRODUCED IN RESPONSE TO VACCINATION WITH RECOMBINANT HBSAG AND INFECTION WITH THE WILD HEPATITIS B VIRUS

Background: Viral hepatitis, particularly hepatitis B virus (HBV) infection remains a major public health problem worldwide and different profiles of IgG subclasses of anti-HBs antibody have been reported to be produced in individuals infected with HBV and those vaccinated with HBsAg. Objective: To evaluate the difference among various profiles of IgG subclasses produced in response to HBV infection and HBsAg observed in HBV positive patients and those vaccinated with HBsAg. Methods: Antibody to hepatitis B surface antigen (HBsAg) was purified by affinity chromatography from sera of 24 normal individuals vaccinated with recombinant HBsAg (rHBsAg) and 18 persons infected with hepatitis B virus (HBV). The isotype and IgG subclass profiles of the purified anti-HBs antibodies were determined by enzyme-linked immunosorbent assay (ELISA) using plates pre-coated with rHBsAg and isotype specific monoclonal antibodies. Results: IgG2 was the predominant subclass of anti-HBs antibody in both groups of individuals followed by IgG4 and IgG1. IgG3 was hardly detectable in the majority of samples tested. Conclusion: No significant differences were observed between the two subject groups with regards to the levels of IgG subclasses and isotypes, suggesting similar antibody responses to rHBsAg and the wild type HBV. Irn J Med Sci 2000; 25(1&2):42-49