RESUMO
Bovine herpesvirus 1 (BoHV-1), a significant pathogen in the alpha-herpesvirus subfamily, primarily infects cattle and causes the upper respiratory disease known as infectious bovine rhinotracheitis (IBR). In silico studies evaluated the BoHV-1 D protein to be non-allergenic, non-toxic, and highly antigenic, highlighting its potential as an antigen for vaccine development. Therefore, this study aimed to evaluate the efficacy of a subunit vaccine using the ectodomain of glycoprotein D (gD34-380) as an antigen. The truncated gD was successfully cloned and expressed in both Escherichia coli (E. coli, termed EgD) and baculovirus (termed BgD) systems, with expected molecular weights of 65â¯kDa and 50â¯kDa, respectively. For the vaccine formulation, the gD proteins were used either alone or in combination with in-house inactivated BoHV-1. Vaccination of mice and bovines showed that baculovirus-expressed gD34-380 accelerated the antibody response. Moreover, the BgD-vaccinated group also showed significantly higher neutralizing antibody levels against BoHV-1 than the control group (p<0.0001). In conclusion, our study found that BgD from BoHV-1 can increase the immune response and enhance vaccine efficacy.
RESUMO
Vaccinations can serve as an important preventive measure against the porcine epidemic diarrhea (PED) virus that currently threatens the swine industry. This study focuses on the development of a fusion protein vaccine, FliC99-mCOE, which combines the N-terminus of flagellin (FliC99) with a modified core neutralizing epitope (mCOE) of PEDV. In silico immunoinformatic analysis confirmed the construct's non-toxic, non-allergenic, and highly antigenic nature. Molecular docking and molecular dynamics (MD) simulations demonstrated FliC99-mCOE's strong binding to the TLR-5 immunological receptor. Repeated exposure simulations and immunological simulations suggested enhanced cell-mediated immunity. Both FliC99-mCOE and an inactivated PEDV vaccine were produced and tested in mice. The results from cell proliferation, ELISA, and neutralization assays indicated that FliC99-mCOE effectively stimulated cellular immunity and neutralized PEDV. We conclude that the FliC99-mCOE fusion protein may serve as a promising vaccine candidate against PEDV.
RESUMO
Flagellin activates the immune system through Toll-like receptor 5 (TLR5) and can work as an adjuvant for subunit vaccines. In this study, we tested the adjuvancy of two different N-terminal fragments of flagellin, (1) FliC99, residues 1-99, and (2) FliC176, residues 1-176, to incorporate larger areas of the hotspot region for potentially higher levels of TLR5 activation and immune response. A truncated version of the VP2 protein (name tVP2, residues 199-356) of the Infectious bursal disease virus (IBDV) was genetically linked to the flagellin constructs, and the immune response was evaluated in chickens. Results showed that both chimeric antigen-adjuvant constructs increased humoral (total IgG titers), cellular and cytokine immune response (IL-4, IFN-γ). The resulting antibody also successfully neutralized IBDV. We conclude that the N-terminus of flagellin can act as an immune activator to enhance vaccine efficacy.