Neutralizing epitopes mapping of human adenovirus type 14 hexon

Area of Science:

• Virology
• Immunology
• Vaccine Development

Background:

• Human adenovirus 14 (HAdV-14) outbreaks cause significant acute respiratory disease (ARD).
• Identifying HAdV-14 neutralizing epitopes is crucial for infection control and surveillance.
• Adenovirus neutralizing epitopes are typically located on the hexon surface.

Purpose of the Study:

• To identify and characterize neutralizing epitopes of HAdV-14.
• To develop chimeric adenoviruses displaying HAdV-14 epitopes for potential bivalent vaccines.

Main Methods:

• Homology modeling to predict epitope locations on the HAdV-14 hexon.
• Synthesis and validation of four predicted epitope peptides (A14R1, A14R2, A14R4, A14R7) using ELISA and neutralization tests (NT).
• Construction of chimeric human adenovirus 3 (HAdV-3) vectors incorporating HAdV-14 epitopes (A14R2A3, A14R4A3) via "antigen capsid-incorporation" strategy.

Main Results:

• All four synthesized peptides (A14R1, A14R2, A14R4, A14R7) were confirmed as neutralizing epitopes.
• Two chimeric adenoviruses, A14R2A3 and A14R4A3, were successfully generated, displaying the respective epitopes on the HAdV-3 hexon surface.
• Antiserum against the chimeric viruses neutralized both HAdV-14 and HAdV-3 infections, with anti-A14R4A3 showing significantly higher titers than controls.

Conclusions:

• The study successfully identified and validated four neutralizing epitopes of HAdV-14.
• Chimeric adenoviruses displaying HAdV-14 epitopes can elicit cross-neutralizing immunity against HAdV-14 and HAdV-3.
• These findings support the development of peptide-based, broadly protective bivalent vaccines against HAdV-14 and HAdV-3.