Sialic Acid Species as a Determinant of the Host Range of Influenza A Viruses

ABSTRACT The distribution of sialic acid (SA) species varies among animal species, but the biological role of this variation is largely unknown. Influenza viruses differ in their ability to recognize SA-galactose (Gal) linkages, depending on the animal hosts from which they are isolated. For example, human viruses preferentially recognize SA linked to Gal by the α2,6(SAα2,6Gal) linkage, while equine viruses favor SAα2,3Gal. However, whether a difference in relative abundance of specific SA species (N-acetylneuraminic acid [NeuAc] andN-glycolylneuraminic acid [NeuGc]) among different animals affects the replicative potential of influenza viruses is uncertain. We therefore examined the requirement for the hemagglutinin (HA) for support of viral replication in horses, using viruses whose HAs differ in receptor specificity. A virus with an HA recognizing NeuAcα2,6Gal but not NeuAcα2,3Gal or NeuGcα2,3Gal failed to replicate in horses, while one with an HA recognizing the NeuGcα2,3Gal moiety replicated in horses. Furthermore, biochemical and immunohistochemical analyses and a lectin-binding assay demonstrated the abundance of the NeuGcα2,3Gal moiety in epithelial cells of horse trachea, indicating that recognition of this moiety is critical for viral replication in horses. Thus, these results provide evidence of a biological effect of different SA species in different animals.

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Amino Acid Residues Contributing to the Substrate Specificity of the Influenza A Virus Neuraminidase

Journal of Virology ◽

10.1128/jvi.73.8.6743-6751.1999 ◽

1999 ◽

Vol 73 (8) ◽

pp. 6743-6751 ◽

Cited By ~ 99

Author(s):

Darwyn Kobasa ◽

Shantha Kodihalli ◽

Ming Luo ◽

Maria R. Castrucci ◽

Isabella Donatelli ◽

...

Keyword(s):

Sialic Acid ◽

Amino Acid ◽

Substrate Specificity ◽

Viral Replication ◽

Active Site ◽

Influenza A ◽

Sialic Acids ◽

Influenza A Viruses ◽

Human Viruses

ABSTRACT Influenza A viruses possess two glycoprotein spikes on the virion surface: hemagglutinin (HA), which binds to oligosaccharides containing terminal sialic acid, and neuraminidase (NA), which removes terminal sialic acid from oligosaccharides. Hence, the interplay between these receptor-binding and receptor-destroying functions assumes major importance in viral replication. In contrast to the well-characterized role of HA in host range restriction of influenza viruses, there is only limited information on the role of NA substrate specificity in viral replication among different animal species. We therefore investigated the substrate specificities of NA for linkages betweenN-acetyl sialic acid and galactose (NeuAcα2-3Gal and NeuAcα2-6Gal) and for different molecular species of sialic acids (N-acetyl and N-glycolyl sialic acids) in influenza A viruses isolated from human, avian, and pig hosts. Substrate specificity assays showed that all viruses had similar specificities for NeuAcα2-3Gal, while the activities for NeuAcα2-6Gal ranged from marginal, as represented by avian and early N2 human viruses, to high (although only one-third the activity for NeuAcα2-3Gal), as represented by swine and more recent N2 human viruses. Using site-specific mutagenesis, we identified in the earliest human virus with a detectable increase in NeuAcα2-6Gal specificity a change at position 275 (from isoleucine to valine) that enhanced the specificity for this substrate. Valine at position 275 was maintained in all later human viruses as well as swine viruses. A similar examination of N-glycolylneuraminic acid (NeuGc) specificity showed that avian viruses and most human viruses had low to moderate activity for this substrate, with the exception of most human viruses isolated between 1967 and 1969, whose NeuGc specificity was as high as that of swine viruses. The amino acid at position 431 was found to determine the level of NeuGc specificity of NA: lysine conferred high NeuGc specificity, while proline, glutamine, and glutamic acid were associated with lower NeuGc specificity. Both residues 275 and 431 lie close to the enzymatic active site but are not directly involved in the reaction mechanism. This finding suggests that the adaptation of NA to different substrates occurs by a mechanism of amino acid substitutions that subtly alter the conformation of NA in and around the active site to facilitate the binding of different species of sialic acid.

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N-Glycolylneuraminic Acid in Animal Models for Human Influenza A Virus

Viruses ◽

10.3390/v13050815 ◽

2021 ◽

Vol 13 (5) ◽

pp. 815

Author(s):

Cindy M. Spruit ◽

Nikoloz Nemanichvili ◽

Masatoshi Okamatsu ◽

Hiromu Takematsu ◽

Geert-Jan Boons ◽

...

Keyword(s):

Sialic Acid ◽

Animal Models ◽

Influenza A ◽

Influenza Virus Infection ◽

Influenza Viruses ◽

Upper Respiratory Tract ◽

Human Influenza ◽

Influenza A Viruses ◽

Sialic Acid Content ◽

Acetylneuraminic Acid

The first step in influenza virus infection is the binding of hemagglutinin to sialic acid-containing glycans present on the cell surface. Over 50 different sialic acid modifications are known, of which N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) are the two main species. Animal models with α2,6 linked Neu5Ac in the upper respiratory tract, similar to humans, are preferred to enable and mimic infection with unadapted human influenza A viruses. Animal models that are currently most often used to study human influenza are mice and ferrets. Additionally, guinea pigs, cotton rats, Syrian hamsters, tree shrews, domestic swine, and non-human primates (macaques and marmosets) are discussed. The presence of NeuGc and the distribution of sialic acid linkages in the most commonly used models is summarized and experimentally determined. We also evaluated the role of Neu5Gc in infection using Neu5Gc binding viruses and cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH)-/- knockout mice, which lack Neu5Gc and concluded that Neu5Gc is unlikely to be a decoy receptor. This article provides a base for choosing an appropriate animal model. Although mice are one of the most favored models, they are hardly naturally susceptible to infection with human influenza viruses, possibly because they express mainly α2,3 linked sialic acids with both Neu5Ac and Neu5Gc modifications. We suggest using ferrets, which resemble humans closely in the sialic acid content, both in the linkages and the lack of Neu5Gc, lung organization, susceptibility, and disease pathogenesis.

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Eco-Epidemiological Evidence of the Transmission of Avian and Human Influenza A Viruses in Wild Pigs in Campeche, Mexico

Viruses ◽

10.3390/v12050528 ◽

2020 ◽

Vol 12 (5) ◽

pp. 528

Author(s):

Brenda Aline Maya-Badillo ◽

Rafael Ojeda-Flores ◽

Andrea Chaves ◽

Saul Reveles-Félix ◽

Guillermo Orta-Pineda ◽

...

Keyword(s):

Influenza A ◽

Influenza Viruses ◽

Influenza A Viruses ◽

Serum Samples ◽

Fragmented Habitats ◽

Wild Pigs ◽

Wide Range ◽

Influenza Transmission ◽

Human Viruses ◽

Positive Results

Influenza, a zoonosis caused by various influenza A virus subtypes, affects a wide range of species, including humans. Pig cells express both sialyl-α-2,3-Gal and sialyl-α-2,6-Gal receptors, which make them susceptible to infection by avian and human viruses, respectively. To date, it is not known whether wild pigs in Mexico are affected by influenza virus subtypes, nor whether this would make them a potential risk of influenza transmission to humans. In this work, 61 hogs from two municipalities in Campeche, Mexico, were sampled. Hemagglutination inhibition assays were performed in 61 serum samples, and positive results were found for human H1N1 (11.47%), swine H1N1 (8.19%), and avian H5N2 (1.63%) virus variants. qRT-PCR assays were performed on the nasal swab, tracheal, and lung samples, and 19.67% of all hogs were positive to these assays. An avian H5N2 virus, first reported in 1994, was identified by sequencing. Our results demonstrate that wild pigs are participating in the exposure, transmission, maintenance, and possible diversification of influenza viruses in fragmented habitats, highlighting the synanthropic behavior of this species, which has been poorly studied in Mexico.

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Infection of Human Airway Epithelium by Human and Avian Strains of Influenza A Virus

Journal of Virology ◽

10.1128/jvi.00384-06 ◽

2006 ◽

Vol 80 (16) ◽

pp. 8060-8068 ◽

Cited By ~ 172

Author(s):

Catherine I. Thompson ◽

Wendy S. Barclay ◽

Maria C. Zambon ◽

Raymond J. Pickles

Keyword(s):

Sialic Acid ◽

Avian Influenza ◽

Influenza A Virus ◽

Airway Epithelium ◽

Influenza A ◽

Cell Types ◽

Influenza Viruses ◽

Apical Surface ◽

Ciliated Cells ◽

Human Viruses

ABSTRACT We describe the characterization of influenza A virus infection of an established in vitro model of human pseudostratified mucociliary airway epithelium (HAE). Sialic acid receptors for both human and avian viruses, α-2,6- and α-2,3-linked sialic acids, respectively, were detected on the HAE cell surface, and their distribution accurately reflected that in human tracheobronchial tissue. Nonciliated cells present a higher proportion of α-2,6-linked sialic acid, while ciliated cells possess both sialic acid linkages. Although we found that human influenza viruses infected both ciliated and nonciliated cell types in the first round of infection, recent human H3N2 viruses infected a higher proportion of nonciliated cells in HAE than a 1968 pandemic-era human virus, which infected proportionally more ciliated cells. In contrast, avian influenza viruses exclusively infected ciliated cells. Although a broad-range neuraminidase abolished infection of HAE by human parainfluenza virus type 3, this treatment did not significantly affect infection by influenza viruses. All human viruses replicated efficiently in HAE, leading to accumulation of nascent virus released from the apical surface between 6 and 24 h postinfection with a low multiplicity of infection. Avian influenza A viruses also infected HAE, but spread was limited compared to that of human viruses. The nonciliated cell tropism of recent human H3N2 viruses reflects a preference for the sialic acid linkages displayed on these cell types and suggests a drift in the receptor binding phenotype of the H3 hemagglutinin protein as it evolves in humans away from its avian virus precursor.

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Role of Sialic Acid Binding Specificity of the 1918 Influenza Virus Hemagglutinin Protein in Virulence and Pathogenesis for Mice

Journal of Virology ◽

10.1128/jvi.02596-08 ◽

2009 ◽

Vol 83 (8) ◽

pp. 3754-3761 ◽

Cited By ~ 50

Author(s):

Li Qi ◽

John C. Kash ◽

Vivien G. Dugan ◽

Ruixue Wang ◽

Guozhong Jin ◽

...

Keyword(s):

Influenza Virus ◽

Sialic Acid ◽

Influenza A ◽

Influenza Pandemic ◽

Binding Specificity ◽

Influenza Viruses ◽

Virulence Determinants ◽

Sialic Acid Binding ◽

1918 Influenza

ABSTRACT The 1918 influenza pandemic caused more than 40 million deaths and likely resulted from the introduction and adaptation of a novel avian-like virus. Influenza A virus hemagglutinins are important in host switching and virulence. Avian-adapted influenza virus hemagglutinins bind sialic acid receptors linked via α2-3 glycosidic bonds, while human-adapted hemagglutinins bind α2-6 receptors. Sequence analysis of 1918 isolates showed hemagglutinin genes with α2-6 or mixed α2-6/α2-3 binding. To characterize the role of the sialic acid binding specificity of the 1918 hemagglutinin, we evaluated in mice chimeric influenza viruses expressing wild-type and mutant hemagglutinin genes from avian and 1918 strains with differing receptor specificities. Viruses expressing 1918 hemagglutinin possessing either α2-6, α2-3, or α2-3/α2-6 sialic acid specificity were fatal to mice, with similar pathology and cellular tropism. Changing α2-3 to α2-6 binding specificity did not increase the lethality of an avian-adapted hemagglutinin. Thus, the 1918 hemagglutinin contains murine virulence determinants independent of receptor binding specificity.

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Emergence of influenza A viruses

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2001.0997 ◽

2001 ◽

Vol 356 (1416) ◽

pp. 1817-1828 ◽

Cited By ~ 154

Author(s):

R. J. Webby ◽

R. G. Webster

Keyword(s):

Intermediate Host ◽

Influenza A ◽

Influenza Viruses ◽

Human Populations ◽

Aquatic Bird ◽

Intermediate Hosts ◽

Aquatic Birds ◽

Influenza A Viruses ◽

Bird Populations ◽

Human Viruses

Pandemic influenza in humans is a zoonotic disease caused by the transfer of influenza A viruses or virus gene segments from animal reservoirs. Influenza A viruses have been isolated from avian and mammalian hosts, although the primary reservoirs are the aquatic bird populations of the world. In the aquatic birds, influenza is asymptomatic, and the viruses are in evolutionary stasis. The aquatic bird viruses do not replicate well in humans, and these viruses need to reassort or adapt in an intermediate host before they emerge in human populations. Pigs can serve as a host for avian and human viruses and are logical candidates for the role of intermediate host. The transmission of avian H5N1 and H9N2 viruses directly to humans during the late 1990s showed that land-based poultry also can serve between aquatic birds and humans as intermediate hosts of influenza viruses. That these transmission events took place in Hong Kong and China adds further support to the hypothesis that Asia is an epicentre for influenza and stresses the importance of surveillance of pigs and live-bird markets in this area.

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Wild Birds in Live Birds Markets: Potential Reservoirs of Enzootic Avian Influenza Viruses and Antimicrobial Resistant Enterobacteriaceae in Northern Egypt

Pathogens ◽

10.3390/pathogens9030196 ◽

2020 ◽

Vol 9 (3) ◽

pp. 196 ◽

Cited By ~ 2

Author(s):

Nehal M. Nabil ◽

Ahmed M. Erfan ◽

Maram M. Tawakol ◽

Naglaa M. Haggag ◽

Mahmoud M. Naguib ◽

...

Keyword(s):

Influenza A ◽

Migratory Birds ◽

Wild Birds ◽

Influenza Viruses ◽

Northern Coast ◽

Influenza A Viruses ◽

E Coli ◽

Ha Gene ◽

Live Bird

Wild migratory birds are often implicated in the introduction, maintenance, and global dissemination of different pathogens, such as influenza A viruses (IAV) and antimicrobial-resistant (AMR) bacteria. Trapping of migratory birds during their resting periods at the northern coast of Egypt is a common and ancient practice performed mainly for selling in live bird markets (LBM). In the present study, samples were collected from 148 wild birds, representing 14 species, which were being offered for sale in LBM. All birds were tested for the presence of AIV and enterobacteriaceae. Ten samples collected from Northern Shoveler birds (Spatula clypeata) were positive for IAV and PCR sub-typing and pan HA/NA sequencing assays detected H5N8, H9N2, and H6N2 viruses in four, four, and one birds, respectively. Sequencing of the full haemagglutinin (HA) gene revealed a high similarity with currently circulating IAV in Egypt. From all the birds, E. coli was recovered from 37.2% and Salmonella from 20.2%, with 66–96% and 23–43% isolates being resistant to at least one of seven selected critically important antimicrobials (CIA), respectively. The presence of enzootic IAV and the wide prevalence of AMR enterobacteriaceae in wild birds highlight the potential role of LBM in the spread of different pathogens from and to wild birds. Continued surveillance of both AIV and antimicrobial-resistant enterobacteriaceae in wild birds’ habitats is urgently needed.

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Influenza A Viruses Control Expression of Proviral Human p53 Isoforms p53β and Δ133p53α

Journal of Virology ◽

10.1128/jvi.07143-11 ◽

2012 ◽

Vol 86 (16) ◽

pp. 8452-8460 ◽

Cited By ~ 22

Author(s):

Olivier Terrier ◽

Virginie Marcel ◽

Gaëlle Cartet ◽

David P. Lane ◽

Bruno Lina ◽

...

Keyword(s):

Virus Infection ◽

Cell Fate ◽

Influenza A ◽

Influenza Virus Infection ◽

Influenza Viruses ◽

Lung Epithelial Cells ◽

Dependent Manner ◽

Influenza A Viruses ◽

P53 Isoforms

Previous studies have described the role of p53 isoforms, including p53β and Δ133p53α, in the modulation of the activity of full-length p53, which regulates cell fate. In the context of influenza virus infection, an interplay between influenza viruses and p53 has been described, with p53 being involved in the antiviral response. However, the role of physiological p53 isoforms has never been explored in this context. Here, we demonstrate that p53 isoforms play a role in influenza A virus infection by using silencing and transient expression strategies in human lung epithelial cells. In addition, with the help of a panel of different influenza viruses from different subtypes, we also show that infection differentially regulates the expressions of p53β and Δ133p53α. Altogether, our results highlight the role of p53 isoforms in the viral cycle of influenza A viruses, with p53β and Δ133p53α acting as regulators of viral production in a p53-dependent manner.

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Cross-Reactive Neuraminidase-Inhibiting Antibodies Elicited by Immunization with Recombinant Neuraminidase Proteins of H5N1 and Pandemic H1N1 Influenza A Viruses

Journal of Virology ◽

10.1128/jvi.00585-15 ◽

2015 ◽

Vol 89 (14) ◽

pp. 7224-7234 ◽

Cited By ~ 31

Author(s):

Wen-Chun Liu ◽

Chia-Ying Lin ◽

Yung-Ta Tsou ◽

Jia-Tsrong Jan ◽

Suh-Chin Wu

Keyword(s):

Influenza Virus ◽

Sialic Acid ◽

Influenza Vaccine ◽

Influenza A ◽

Expression System ◽

Influenza Viruses ◽

Pandemic H1n1 ◽

Influenza A Viruses ◽

Homologous Virus ◽

Universal Influenza Vaccine

ABSTRACTNeuraminidase (NA), an influenza virus envelope glycoprotein, removes sialic acid from receptors for virus release from infected cells. For this study, we used a baculovirus-insect cell expression system to construct and purify recombinant NA (rNA) proteins of H5N1 (A/Vietnam/1203/2004) and pandemic H1N1 (pH1N1) (A/Texas/05/2009) influenza viruses. BALB/c mice immunized with these proteins had high titers of NA-specific IgG and NA-inhibiting (NI) antibodies against H5N1, pH1N1, H3N2, and H7N9 viruses. H5N1 rNA immunization resulted in higher quantities of NA-specific antibody-secreting B cells against H5N1 and heterologous pH1N1 viruses in the spleen. H5N1 rNA and pH1N1 rNA immunizations both provided complete protection against homologous virus challenges, with H5N1 rNA immunization providing better protection against pH1N1 virus challenges. Cross-reactive NI antibodies were further dissected via pH1N1 rNA protein immunizations with I149V (NA with a change of Ile to Val at position 149), N344Y, and I365T/S366N NA mutations. The I365T/S366N mutation of pH1N1 rNA enhanced cross-reactive NI antibodies against H5N1, H3N2, and H7N9 viruses. It is our hope that these findings provide useful information for the development of an NA-based universal influenza vaccine.IMPORTANCENeuraminidase (NA) is an influenza virus enzymatic protein that cleaves sialic acid linkages on infected cell surfaces, thus facilitating viral release and contributing to viral transmission and mucus infection. In currently available inactivated or live, attenuated influenza vaccines based on the antigenic content of hemagglutinin proteins, vaccine efficacy can be contributed partly through NA-elicited immune responses. We investigated the NA immunity of different recombinant NA (rNA) proteins associated with pH1N1 and H5N1 viruses. Our results indicate that H5N1 rNA immunization induced more potent cross-protective immunity than pH1N1 rNA immunization, and three mutated residues, I149V, I365T, and S366N, near the NA enzyme active site(s) are linked to enhanced cross-reactive NA-inhibiting antibodies against heterologous and heterosubtypic influenza A viruses. These findings provide useful information for the development of an NA-based universal influenza vaccine.

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Influenza binds phosphorylated glycans from human lung

Science Advances ◽

10.1126/sciadv.aav2554 ◽

2019 ◽

Vol 5 (2) ◽

pp. eaav2554 ◽

Cited By ~ 20

Author(s):

Lauren Byrd-Leotis ◽

Nan Jia ◽

Sucharita Dutta ◽

Jessica F. Trost ◽

Chao Gao ◽

...

Keyword(s):

Sialic Acid ◽

Influenza A ◽

Human Lung ◽

Species Specificity ◽

Influenza Viruses ◽

Surface Markers ◽

Influenza A Viruses ◽

Synthetic Receptor ◽

Glycan Receptors ◽

Sialic Acid Linkage

Influenza A viruses can bind sialic acid–terminating glycan receptors, and species specificity is often correlated with sialic acid linkage with avian strains recognizing α2,3-linked sialylated glycans and mammalian strains preferring α2,6-linked sialylated glycans. These paradigms derive primarily from studies involving erythrocyte agglutination, binding to synthetic receptor analogs or binding to undefined surface markers on cells or tissues. Here, we present the first examination of the N-glycome of the human lung for identifying natural receptors for a range of avian and mammalian influenza viruses. We found that the human lung contains many α2,3- and α2,6-linked sialylated glycan determinants bound by virus, but all viruses also bound to phosphorylated, nonsialylated glycans.

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