An epitope on the stem region of hemagglutinin of H1N1 influenza A virus recognized by neutralizing monoclonal antibody

• Published in: Biochemical and biophysical research communications 2019-10, Vol.518 (2), p.319-324
• Main Authors: Yan, Liting, Wang, Haifang, Sun, Lijun, Liu, Yang, Sun, Jingying, Zhao, Xiangrong, Li, Yan, Xie, Xin, Hu, Jun
• Format: Article
• Language: English
• Subjects: Epitope peptide; Hemagglutinin; Influenza virus; Neutralizing antibodies; Vaccine
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2019.08.055

Influenza A viruses are a major threat to human health and inflict a significant public health challenge worldwide. Hemagglutinin (HA) is the main contributor to the infectivity of the virus and is a potential target for the development of antiviral therapeutic agents. The stem region of HA, which has been shown to be conserved, is the primary target in the development of antibody-based therapeutic strategies and preventive tools. Here, we confirmed the neutralizing activity and prophylactic efficacy of murine monoclonal antibody PR8-25 as well as Western blot analysis of different influenza virus strains. Then, we identified the epitope of PR8-25, 328-LRMVTGLRNIPS-339, by phage-displayed 12-mer random peptide library. The identified epitope targeted in the stem region of HA, specifically at the C-terminal of the HA1 fragment. This result suggest that the identified epitope may be a potential basis for antiviral drugs and stem-based universal influenza vaccines. •Monoclonal antibody PR8-25 (MAb PR8-25) shown neutralizing activity both in vitro and in vivo.•MAb PR8-25 shown reactivity with H1 subtype of influenza virus.•The epitope of MAb PR8-25, 328-339aa, targeted in the stem region of HA and located at the C-terminal of the HA1 fragment.