Previous studies have shown that 5-10% of Hepatitis B Virus vaccine recipients produce none
or to few antibodies after a standard immunization with 3 vaccines. These individuals are
defined as non-responders. The investigators wish to investigate if mounting another kind of
immune response, called the cellular immune (CMI) response, protects these non-responders.
1. To estimate the CMI response in serologic non-responders after receiving a standard
course of HBV immunization
2. To establish the prevalence of serological non-responders after a standard course of HBV
3. To assess the safety of the vaccine.
4. Evaluate predictors of serologic non-response in young, healthy individuals receiving a
standard course of HBV immunization
5. To compare the immunological profile before and after a standard HBV vaccination regimen
on non-responders and responders
6. Establish a rapid test for measuring CMI after being HBV vaccinated.
A total of 400 healthy volunteers receive a standard course of immunization with a combined
hepatitis A and B vaccine (Twinrix®) at 0, 1, and 6 months. Blood is drawn at 0 and 8 months
from all participants. The blood will be analysed to see if there is antibodies or/and if
there is mounted a cellular immune response by measuring on parameters called cytokines.