Adaptive immune response to a wild boar-derived recombinant hepatitis e virus capsid protein challenge in pigs

Hepatitis E virus genotype 3 (HEV-3) is a zoonotic pathogen capable of infecting human, porcine, and other animal hosts. Despite a broad host range and abundance of species that act as reservoirs for human infections, no commercially available animal vaccines against HEV-3 are currently available. In the present study, we tested the capacity of recombinant aa 112-608 wild boar-derived HEV-3 capsid protein (rORF2p) to induce an immune response in immunized pigs. Four 6 week old pigs were administered 1 ml of 200 μg/ml rORF2p, followed by booster administration after 14 days. Blood samples were collected until 28 days after initial immunization. Dominant cell phenotypes and anti-HEV IgG concentrations were determined. A significant anti-HEV IgG, monocyte/macrophage, B cell and T cell response has been detected in immunized pigs. In turn, our findings suggest the capacity of rORF2p to elicit an immune response in pigs, suggesting the potential for its use as a vaccine candidate.