Vaccine to Inhibit Autochthonous Transmission of Hepatitis (VaccinATE)

Introduction and aim Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide. In Germany, genotype 3 (GT3) is most prevalent and pigs are the main reservoir of this genotype. HEV GT3 is mainly transmitted to humans through consumption of contaminated meat products. Therefore, vaccination of pigs against HEV could consequently prevent the transmission of HEV to humans. Here, we aimed to identify the most suitable immunogen and immunization strategy for vaccination against HEV.

Methods We selected eight different protein- or DNA-based HEV vaccines to compare their efficacy, using rabbits as antibody donors. Antibody responses of the animals were analyzed for binding of HEV by means of ELISA and immunofluorescence. Furthermore, the antibody was functionally assessed utilizing neutralization assays. The avidity of antibodies from rabbit sera to the HEV antigen was measured using a urea-based ELISA.

Results and conclusion We identified that vaccination of rabbits with all different vaccines elicited anti-HEV IgG antibodies. All the antibodies have neutralization activity against HEV GT3. Furthermore, using immunofluorescence staining, we revealed that antibodies in the rabbit sera bind to HEV transfected HepG2 cells. According to the results of our urea-based ELISA, the anti-HEV IgG antibodies from inoculated rabbits had different avidity indices depending on the type of vaccine used. In this project, we could evaluate different vaccination technologies against HEV in rabbits. Based on our findings, the most suitable immunogens have been identified, paving the way for future studies on the immunization of pigs.

Publication History

Article published online:
18 January 2023