OmniVira

H7N9 influenza viruses interact preferentially with α2,3-linked sialic acids and bind weakly to α2,6-linked sialic acids.

Irene Ramos1 Florian Krammer1 Rong Hai1 Domingo Aguilera1 Dabeiba Bernal-Rubio1 John Steel2 Adolfo García-Sastre3,4,1 Ana Fernandez-Sesma3,1
Affiliations 4 institutions
  1. Department of Microbiology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue New York, NY 10029, USA.
  2. Department of Microbiology and Immunology, Emory University School of Medicine, GA 30322, USA.
  3. Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue New York, NY 10029, USA.
  4. Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue New York, NY 10029, USA.
PMID23950563 DOI10.1099/vir.0.056184-0 Year2013 Journal The Journal of general virology J Gen Virol Languageeng Statusppublish

Abstract

The recent human outbreak of H7N9 avian influenza A virus has caused worldwide concerns. Receptor binding specificity is critical for viral pathogenicity, and still not thoroughly studied for this emerging virus. Here, we evaluated the receptor specificity of the haemagglutinin (HA) of two human H7N9 isolates (A/Shanghai/1/13 and A/Anhui/1/13) through a solid-phase binding assay and a flow cytometry-based assay. In addition, we compared it with those from several HAs from human and avian influenza viruses. We observed that the HAs from the novel H7 isolates strongly interacted with α2,3-linked sialic acids. Importantly, they also showed low levels of binding to α2,6-linked sialic acids, but significantly higher than other avian H7s.

Supporting text Virus Host Location
Host-Pathogen Interactions 55 Viral Tropism 45 Animals 1948 Birds 212 China 229 Hemagglutinin Glycoproteins, Influenza Virus 180 Humans 1440 Influenza A Virus, H7N9 Subtype 87 Influenza in Birds 341 Influenza, Human 286 Receptors, Virus 204 Sialic Acids 29

Evidence records

2 total
Functional Mechanism
2 records · 2 evidence types
Evidence type Receptor Usage
1 records
OVE1544 Receptor Usage
Key finding

H7N9 influenza A virus haemagglutinin preferentially binds α2,3-linked sialic acid receptors and exhibits weaker interaction with α2,6-linked sialic acids.

Virus
Influenza A virus H7N9
Host
human Homo sapiens Experimental system
Location
Not specified
Supporting text

Here, we evaluated the receptor specificity of the haemagglutinin (HA) of two human H7N9 isolates (A/Shanghai/1/13 and A/Anhui/1/13) through a solid-phase binding assay and a flow cytometry-based assay. We observed that the HAs from the novel H7 isolates strongly interacted with α2,3-linked sialic acids. Importantly, they also showed low levels of binding to α2,6-linked sialic acids, but significantly higher than other avian H7s.

Method
solid-phase binding assay | flow cytometry-based assay
Receptors
α2,3-linked sialic acid | α2,6-linked sialic acid
Evidence type Molecular Adaptation
1 records
OVE1545 Molecular Adaptation
Key finding

Human H7N9 influenza A isolates A/Shanghai/1/13 and A/Anhui/1/13 exhibit shifted receptor-binding characteristics toward human-type α2,6-linked sialic acids compared with typical avian H7 viruses, indicating molecular adaptation associated with human infection.

Virus
Influenza A virus H7N9
Host
Not specified
Location
Not specified
Supporting text

Importantly, they also showed low levels of binding to α2,6-linked sialic acids, but significantly higher than other avian H7s.

Genes or proteins
haemagglutinin (HA)
Receptors
α2,3-linked sialic acids | α2,6-linked sialic acids
Mechanism types
receptor binding | host-range expansion