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Preferential recognition of avian-like receptors in human influenza A H7N9 viruses.

ABSTRACT: The 2013 outbreak of avian-origin H7N9 influenza in eastern China has raised concerns about its ability to transmit in the human population. The hemagglutinin glycoprotein of most human H7N9 viruses carries Leu(226), a residue linked to adaptation of H2N2 and H3N2 pandemic viruses to human receptors. However, glycan array analysis of the H7 hemagglutinin reveals negligible binding to humanlike ?2-6-linked receptors and strong preference for a subset of avian-like ?2-3-linked glycans recognized by all avian H7 viruses. Crystal structures of H7N9 hemagglutinin and six hemagglutinin-glycan complexes have elucidated the structural basis for preferential recognition of avian-like receptors. These findings suggest that the current human H7N9 viruses are poorly adapted for efficient human-to-human transmission.

SUBMITTER: Xu R

PROVIDER: S-EPMC3954636 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Preferential recognition of avian-like receptors in human influenza A H7N9 viruses.

Xu Rui R de Vries Robert P RP Zhu Xueyong X Nycholat Corwin M CM McBride Ryan R Yu Wenli W Paulson James C JC Wilson Ian A IA

Science (New York, N.Y.) 20131201 6163

The 2013 outbreak of avian-origin H7N9 influenza in eastern China has raised concerns about its ability to transmit in the human population. The hemagglutinin glycoprotein of most human H7N9 viruses carries Leu(226), a residue linked to adaptation of H2N2 and H3N2 pandemic viruses to human receptors. However, glycan array analysis of the H7 hemagglutinin reveals negligible binding to humanlike α2-6-linked receptors and strong preference for a subset of avian-like α2-3-linked glycans recognized b ...[more]

PMID: 24311689

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