Humoral immune response to hepatitis B vaccination: A laboratory practical for medical and bioscience undergraduates

Abstract

From 1991 to 1997, laboratory exercises have been conducted using an enzyme-linked immunosorbent assay (ELISA) kit to determine the presence of antibodies to hepatitis B virus (HBV) surface antigen among a total of 690 medical and science undergraduates aged 18-25 years. Out of 431 students who received at least the full course of three doses of HBV vaccine, 376 (87.2%) tested positive for HBV antibodies, demonstrating the immunogenicity of the current recombinant yeast-derived vaccines. However, 12.8% (55/431) of vaccinees remained seronegative, thereby indicating the need for serological testing to ascertain seroconversion following HBV vaccination. Only 66.7% (18/27) of subjects who received less than three doses of HBV vaccine developed HBV antibodies, thus emphasizing the necessity for the complete vaccination protocol to achieve an optimal antibody response. The vast majority of non-vaccinated students (91.1% or 205/225) were seronegative, and advised HBV immunization. Particularly in regions such as Singapore where HBV infection is endemic, this practical study has good health education value, reinforces the principles and applications of the ELISA technique, and integrates certain key concepts of virology, immunology, molecular biology and medicine.