Rescue of a H3N2 influenza virus containing a deficient neuraminidase protein by a hemagglutinin with a low receptor-binding affinity

PLoS One. 2012;7(5):e33880. doi: 10.1371/journal.pone.0033880. Epub 2012 May 1.


Influenza viruses possess at their surface two glycoproteins, the hemagglutinin and the neuraminidase, of which the antagonistic functions have to be well balanced for the virus to grow efficiently. Ferraris et al. isolated in 2003-2004 viruses lacking both a NA gene and protein (H3NA- viruses) (Ferraris O., 2006, Vaccine, 24(44-46):6656-9). In this study we showed that the hemagglutinins of two of the H3NA- viruses have reduced affinity for SAα2.6Gal receptors, between 49 and 128 times lower than that of the A/Moscow/10/99 (H3N2) virus and no detectable affinity for SAα2.3Gal receptors. We also showed that the low hemagglutinin affinity of the H3NA- viruses compensates for the lack of NA activity and allows the restoration of the growth of an A/Moscow/10/99 virus deficient in neuraminidase. These observations increase our understanding of H3NA- viruses in relation to the balance between the functional activities of the neuraminidase and hemagglutinin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding, Competitive
  • Cell Line
  • Flow Cytometry
  • Genetic Complementation Test
  • Hemagglutinin Glycoproteins, Influenza Virus / genetics
  • Hemagglutinin Glycoproteins, Influenza Virus / metabolism*
  • Humans
  • Influenza A Virus, H3N2 Subtype / genetics
  • Influenza A Virus, H3N2 Subtype / growth & development
  • Influenza A Virus, H3N2 Subtype / metabolism*
  • Kinetics
  • Molecular Sequence Data
  • Mutation
  • Neuraminidase / genetics
  • Neuraminidase / metabolism*
  • Protein Binding
  • Receptors, Cell Surface / metabolism*
  • Receptors, Virus / metabolism
  • Transfection


  • HN protein receptor
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Receptors, Cell Surface
  • Receptors, Virus
  • sialic acid receptor
  • Neuraminidase

Associated data

  • GENBANK/JF421757
  • GENBANK/JF421758