Structural Biology of Influenza Hemagglutinin: An Amaranthine Adventure

Viruses. 2020 Sep 22;12(9):1053. doi: 10.3390/v12091053.


Hemagglutinin (HA) glycoprotein is an important focus of influenza research due to its role in antigenic drift and shift, as well as its receptor binding and membrane fusion functions, which are indispensable for viral entry. Over the past four decades, X-ray crystallography has greatly facilitated our understanding of HA receptor binding, membrane fusion, and antigenicity. The recent advances in cryo-EM have further deepened our comprehension of HA biology. Since influenza HA constantly evolves in natural circulating strains, there are always new questions to be answered. The incessant accumulation of knowledge on the structural biology of HA over several decades has also facilitated the design and development of novel therapeutics and vaccines. This review describes the current status of the field of HA structural biology, how we got here, and what the next steps might be.

Keywords: antibody; antigenicity; escape mutations; evolution; hemagglutinin; host receptor binding; influenza virus; membrane fusion; sialylated glycans; vaccine.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Antibodies, Viral / immunology
  • Drug Design
  • Hemagglutinin Glycoproteins, Influenza Virus / chemistry*
  • Hemagglutinin Glycoproteins, Influenza Virus / genetics
  • Hemagglutinin Glycoproteins, Influenza Virus / immunology*
  • Humans
  • Immunogenicity, Vaccine
  • Influenza Vaccines
  • Influenza, Human* / genetics
  • Membrane Fusion
  • Models, Molecular
  • Protein Binding
  • Protein Conformation
  • Virus Internalization


  • Antibodies, Viral
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Influenza Vaccines