In silico identification and characterization of common epitope-based peptide vaccine for Nipah and Hendra viruses

Objective: To explore a common B-and T-cell epitope-based vaccine that can elicit an immune response against encephalitis causing genus Henipaviruses, Hendra virus(He V) and Nipah virus(Ni V). Methods: Membrane proteins F, G and M of He V and Ni V were retrieved from the protein database and subjected to different bioinformatics tools to predict antigenic B-cell epitopes. Best B-cell epitopes were then analyzed to predict their T-cell antigenic potentiality. Antigenic B-and T-cell epitopes that shared maximum identity with He V and Ni V were selected. Stability of the selected epitopes was predicted. Finally, the selected epitopes were subjected to molecular docking simulation with HLA-DR to confirm their antigenic potentiality in silico. Results: One epitope from G proteins, one from M proteins and none from F proteins were selected based on their antigenic potentiality. The epitope from the G proteins was stable whereas that from M was unstable. The M-epitope was made stable by adding flanking dipeptides. The 15-mer G-epitope(VDPLRVQWRNNSVIS) showed at least 66% identity with all Ni V and He V G protein sequences, while the 15-mer M-epitope(GKLEFRRNNAIAFKG) with the dipeptide flanking residues showed 73% identity with all Ni V and He V M protein sequences available in the database. Molecular docking simulation with most frequent MHC class-II(MHC II) and class-I(MHC I) molecules showed that these epitopes could bind within HLA binding grooves to elicit an immune response. Conclusions: Data in our present study revealed the notion that the epitopes from G and M proteins might be the target for peptide-based subunit vaccine design against He V and Ni V. However, the biochemical analysis is necessary to experimentally validate the interaction of epitopes individually with the MHC molecules through elucidation of immunity induction.