Unique Structural Features of Influenza Virus H15 Hemagglutinin
Netanel Tzarum1, Ryan McBride2, Corwin M Nycholat2
1Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA.
Journal of Virology
|April 14, 2017
Summary
Influenza A H15 hemagglutinin (HA) shows unique structural features and a strong preference for avian receptors. Further surveillance of H15 viruses is crucial due to their potential for global spread and enhanced disease in mammals.
Area of Science:
- Virology, Structural Biology, and Immunology
- Characterization of novel influenza A virus hemagglutinin subtypes
Background:
- Influenza A H15 viruses belong to a group of avian influenza viruses (H7-H10-H15) with limited prior isolation and geographical distribution.
- Recent isolations suggest a potential for wider global spread, necessitating a deeper understanding of H15 virus characteristics.
- Previous human infections by related avian influenza subtypes (H7N9, H10N8) highlight the importance of monitoring emerging strains.
Purpose of the Study:
- To elucidate the structural features and receptor-binding specificity of the Influenza A H15 hemagglutinin (HA).
- To assess the potential implications of H15 HA structure for viral evolution, antigenicity, and host adaptation.
- To provide data supporting enhanced global surveillance of H15 viruses as a potential emerging threat.
Main Methods:
- Glycan array analysis to determine receptor binding preferences of the H15 HA.
- X-ray crystallography to determine the three-dimensional structure of the H15 HA.
- Comparative structural analysis of H15 HA with other group 2 HA subtypes (e.g., H7N9).
Main Results:
- H15 HA exhibits a high preference for avian-type receptors, distinct from human-adapted influenza viruses.
- The H15 HA structure reveals unique insertions in the 150-loop and 260-loop, contributing to a wider head domain compared to other HAs.
- The structural findings suggest potential for increased antigenic variation and enhanced interaction with host receptors.
Conclusions:
- The H15 hemagglutinin possesses unique structural and receptor-binding properties that differentiate it from other influenza subtypes.
- The observed features, including the elongated loops and wider head domain, may influence viral transmission, antigenicity, and pathogenicity.
- Continued characterization and immune surveillance of H15 viruses are essential for monitoring their global spread and potential impact on public health.
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