Mobility-Based Quantification of Multivalent Virus-Receptor Interactions: New Insights Into Influenza A Virus Binding Mode

ABSTRACT Influenza A(H7N9) viruses have caused a large number of zoonotic infections since their emergence in 2013. They remain a public health concern due to the repeated high levels of infection with these viruses and their perceived pandemic potential. A major factor that determines influenza A virus fitness and therefore transmissibility is the interaction of the surface glycoproteins hemagglutinin (HA) and neuraminidase (NA) with the cell surface receptor sialic acid. Typically, the HA is responsible for binding to the sialic acid to allow virus internalization and the NA is a sialidase responsible for cleaving sialic acid to aid virus spread and release. N9 NA has previously been shown to have receptor binding properties mediated by a sialic acid binding site, termed the hemadsorption (Hb) site, which is discrete from the enzymatically active sialidase site. This study investigated the N9 NA from a zoonotic H7N9 virus strain in order to determine its possible role in virus receptor binding. We demonstrate that this N9 NA has an active Hb site which binds to sialic acid, which enhances overall virus binding to sialic acid receptor analogues. We also show that the N9 NA can also contribute to receptor binding due to unusual kinetic characteristics of the sialidase site which specifically enhance binding to human-like α2,6-linked sialic acid receptors. IMPORTANCE The interaction of influenza A virus glycoproteins with cell surface receptors is a major determinant of infectivity and therefore transmissibility. Understanding these interactions is important for understanding which factors are necessary to determine pandemic potential. Influenza A viruses generally mediate binding to cell surface sialic acid receptors via the hemagglutinin (HA) glycoprotein, with the neuraminidase (NA) glycoprotein being responsible for cleaving the receptor to allow virus release. Previous studies showed that the NA proteins of the N9 subtype can bind sialic acid via a separate binding site distinct from the sialidase active site. This study demonstrates for purified protein and virus that the NA of the zoonotic H7N9 viruses has a binding capacity via both the secondary binding site and unusual kinetic properties of the sialidase site which promote receptor binding via this site and which enhance binding to human-like receptors. This could have implications for understanding human-to-human transmission of these viruses.

Download Full-text

Kinetic analysis of the influenza A virus HA/NA balance reveals contribution of NA to virus-receptor binding and NA-dependent rolling on receptor-containing surfaces

PLoS Pathogens ◽

10.1371/journal.ppat.1007233 ◽

2018 ◽

Vol 14 (8) ◽

pp. e1007233 ◽

Cited By ~ 37

Author(s):

Hongbo Guo ◽

Huib Rabouw ◽

Anne Slomp ◽

Meiling Dai ◽

Floor van der Vegt ◽

...

Keyword(s):

Kinetic Analysis ◽

Influenza A Virus ◽

Receptor Binding ◽

Influenza A ◽

Virus Receptor

Download Full-text

Influenza A Virus-Binding Activity of Glycoglycerolipids of Aquatic Bacteria

The Journal of Biochemistry ◽

10.1093/oxfordjournals.jbchem.a022594 ◽

2000 ◽

Vol 127 (2) ◽

pp. 191-198 ◽

Cited By ~ 20

Author(s):

K. Nakata ◽

C.-T. Guo ◽

M. Matsufuji ◽

A. Yoshimoto ◽

M. Trmgnlri ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Binding Activity ◽

Virus Binding ◽

Aquatic Bacteria

Download Full-text

Comparison of influenza A virus and formyl-methionyl-leucyl- phenylalanine activation of the human neutrophil

Blood ◽

10.1182/blood.v79.4.1049.1049 ◽

1992 ◽

Vol 79 (4) ◽

pp. 1049-1057 ◽

Cited By ~ 1

Author(s):

KL Hartshorn ◽

DE Daigneault ◽

MR White ◽

M Tuvin ◽

JL Tauber ◽

...

Keyword(s):

Influenza A Virus ◽

Respiratory Burst ◽

Human Neutrophil ◽

Influenza A ◽

Actin Polymerization ◽

Cell Activation ◽

Protein Kinase Inhibitors ◽

Induced Response ◽

Virus Binding ◽

Subsequent Increase

Abstract Influenza A virus (IAV) activates the human neutrophil, but induces a dysfunctional state as well. Cell activation may contribute to the containment of the virus and/or cause local tissue damage. Certain features of the neutrophil activation response elicited by IAV are distinctive when compared with that triggered by formyl-methyl-leucyl- phenylalanine (FMLP). An atypical respiratory burst response occurs in which hydrogen peroxide, but no superoxide, is formed. This unusual respiratory burst stoichiometry persists despite marked priming of the IAV-induced response. A comprehensive examination of the activation cascade initiated by these stimuli failed to show an explanation for these differences. Both IAV and FMLP comparably stimulate inositol trisphosphate and phosphatidic acid production. The subsequent increase in intracellular calcium (Ca2+i) upon FMLP stimulation was more dependent on extracellular Ca2+ than with IAV activation, but both stimuli induced Ca2+ influx. FMLP and IAV exhibited equal susceptibility to inhibition by protein kinase inhibitors in eliciting the respiratory burst, and actin polymerization occurred in response to each agonist. A possible explanation for the anomalous respiratory burst induced by IAV is that O2- is generated at an intracellular site inaccessible to assay, and/or virus binding to sialic acid constituents of the plasma membrane alters the O2- generating capacity of the respiratory burst oxidase; evidence for each mechanism is offered.

Download Full-text

N-Acetylneuraminyllactosylceramide, GM3-NeuAc, a new influenza A virus receptor which mediates the adsorption-fusion process of viral infection. Binding specificity of influenza virus A/Aichi/2/68 (H3N2) to membrane-associated GM3 with different molecular species of sialic acid.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)89596-5 ◽

1985 ◽

Vol 260 (3) ◽

pp. 1362-1365 ◽

Cited By ~ 3

Author(s):

Y Suzuki ◽

M Matsunaga ◽

M Matsumoto

Keyword(s):

Influenza Virus ◽

Sialic Acid ◽

Viral Infection ◽

Influenza A Virus ◽

Molecular Species ◽

Influenza A ◽

Binding Specificity ◽

Fusion Process ◽

Virus Receptor ◽

Influenza Virus A

Download Full-text

The immunomodulatory CEA cell adhesion molecule 6 (CEACAM6/CD66c) is a candidate receptor for the influenza A virus

10.1101/104026 ◽

2017 ◽

Author(s):

Shah Kamranur Rahman ◽

Mairaj Ahmed Ansari ◽

Pratibha Gaur ◽

Imtiyaz Ahmad ◽

Chandrani Chakravarty ◽

...

Keyword(s):

Cell Surface ◽

Influenza A Virus ◽

Influenza A ◽

Virus Entry ◽

Semipermeable Membrane ◽

Host Cells ◽

Lung Cells ◽

Membrane Glycoprotein ◽

Virus Binding ◽

Host Membrane

AbstractTo establish a productive infection in host cells, viruses often use one or multiple host membrane glycoprotein as their receptors. For Influenza A virus (IAV) such a glycoprotein receptor has not been described, to date. Here we show that IAV is using the host membrane glycoprotein CD66c as a receptor for entry into human epithelial lung cells. Neuraminidase (NA), a viral spike protein binds to CD66c on the cell surface during IAV entry into the host cells. Lung cells overexpressing CD66c showed an increase in virus binding and subsequent entry into the cell. Upon comparison, CD66c demonstrated higher binding capacity than other membrane glycoproteins (EGFR and DC-SIGN) reported earlier to facilitate IAV entry into host cells. siRNA mediated knockdown of CD66c from lung cells inhibited virus binding on cell surface and entry into cells. Blocking CD66c by antibody on the cell surface resulted in decreased virus entry. We found CD66c is a specific glycoprotein receptor for influenza A virus that did not affect entry of non-IAV RNA virus (Hepatitis C virus). Finally, IAV pre-incubated with recombinant CD66c protein when administered intranasally in mice showed decreased cytopathic effects in mice lungs. This publication is the first to report CD66c (CEACAM6) as a glycoprotein receptor for Influenza A virus.Significance StatementCells are enclosed by a semipermeable membrane that allows selective exchange of biomolecules between cells and their surroundings. A set of specialized proteins in this semipermeable membrane, work like gatekeepers to the cell and regulate entry of these biomolecules. One class of such surface proteins is termed as receptors. Viruses bind to one or more of these receptors and manipulate gatekeepers for their own successful entry into host-cells. A membrane protein that influenza A virus (Flu virus) uses for entry into the cells was not discovered till date. This study reports for the first time, a receptor for influenza A virus, that was sought after by researchers for decades. The viral receptor is a promising target that can be used to inhibit virus entry into host cells.

Download Full-text