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de Vries E, Du W, Guo H, de Haan CA. Influenza A Virus Hemagglutinin-Neuraminidase-Receptor Balance: Preserving Virus Motility. Trends Microbiol 2020; 28:57-67. [PMID: 31629602 PMCID: PMC7172302 DOI: 10.1016/j.tim.2019.08.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/29/2019] [Accepted: 08/30/2019] [Indexed: 12/14/2022]
Abstract
Influenza A viruses (IAVs) occasionally cross the species barrier and adapt to novel host species. This requires readjustment of the functional balance of the sialic acid receptor-binding hemagglutinin (HA) and the receptor-destroying neuraminidase (NA) to the sialoglycan-receptor repertoire of the new host. Novel techniques have revealed mechanistic details of this HA-NA-receptor balance, emphasizing a previously underappreciated crucial role for NA in driving the motility of receptor-associated IAV particles. Motility enables virion penetration of the sialylated mucus layer as well as attachment to, and uptake into, underlying epithelial cells. As IAVs are essentially irreversibly bound in the absence of NA activity, the fine-tuning of the HA-NA-receptor balance rather than the binding avidity of IAV particles per se is an important factor in determining host species tropism.
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Affiliation(s)
- Erik de Vries
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands.
| | - Wenjuan Du
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Hongbo Guo
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Cornelis A.M. de Haan
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands,Correspondence:
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2
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Kosik I, Yewdell JW. Influenza Hemagglutinin and Neuraminidase: Yin⁻Yang Proteins Coevolving to Thwart Immunity. Viruses 2019; 11:E346. [PMID: 31014029 PMCID: PMC6520700 DOI: 10.3390/v11040346] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/11/2019] [Accepted: 04/13/2019] [Indexed: 01/04/2023] Open
Abstract
Influenza A virions possess two surface glycoproteins-the hemagglutinin (HA) and neuraminidase (NA)-which exert opposite functions. HA attaches virions to cells by binding to terminal sialic acid residues on glycoproteins/glycolipids to initiate the infectious cycle, while NA cleaves terminal sialic acids, releasing virions to complete the infectious cycle. Antibodies specific for HA or NA can protect experimental animals from IAV pathogenesis and drive antigenic variation in their target epitopes that impairs vaccine effectiveness in humans. Here, we review progress in understanding HA/NA co-evolution as each acquires epistatic mutations to restore viral fitness to mutants selected in the other protein by host innate or adaptive immune pressure. We also discuss recent exciting findings that antibodies to HA can function in vivo by blocking NA enzyme activity to prevent nascent virion release and enhance Fc receptor-based activation of innate immune cells.
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Affiliation(s)
- Ivan Kosik
- Laboratory of Viral Diseases, NIAID, NIH, Bethesda, MD 20892, USA.
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3
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Wang YF, Chang CF, Tsai HP, Chi CY, Su IJ, Wang JR. Glycan-binding preferences and genetic evolution of human seasonal influenza A(H3N2) viruses during 1999-2007 in Taiwan. PLoS One 2018; 13:e0196727. [PMID: 29746492 PMCID: PMC5945028 DOI: 10.1371/journal.pone.0196727] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 04/18/2018] [Indexed: 01/01/2023] Open
Abstract
It is generally agreed that human influenza virus preferentially binds to α-2,6-linked sialic acid-containing receptors, and mutations that change the binding preference may alter virus infectivity and host tropism. Limited information is available on the glycan-binding specificity of epidemic influenza viruses. In this study, we systemically investigated the glycan-binding preferences of human influenza A(H3N2) viruses isolated from 1999 to 2007 in Taiwan using a high-throughput carbohydrate array. The binding patterns of 37 H3N2 viruses were classified into three groups with significant binding-pattern variations. The results showed that the carbohydrate-binding patterns of H3N2 varied over time. A phylogenetic analysis of the hemagglutinin gene also revealed progressive drift year to year. Of note, the viruses that caused large outbreaks in 1999 and 2003 showed glycan-binding preferences to both α-2,3 and α-2,6 sialylated glycans. Twenty amino acid substitutions were identified primarily at antigenic sites that might contribute to H3N2 virus evolution and the change in the glycan-binding patterns. This study provides not only a systematic analysis of the receptor-binding specificity of influenza clinical isolates but also information that could help to monitor the outbreak potential and virus evolution of influenza viruses.
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Affiliation(s)
- Ya-Fang Wang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan.,Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Chuan-Fa Chang
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Huey-Pin Tsai
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Chia-Yu Chi
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan.,Department of Pediatrics, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Ih-Jen Su
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan.,Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Jen-Ren Wang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan.,Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.,Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan
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4
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Abstract
Influenza is an acute respiratory illness, caused by influenza A, B, and C viruses, that occurs in local outbreaks or seasonal epidemics. Clinical illness follows a short incubation period and presentation ranges from asymptomatic to fulminant, depending on the characteristics of both the virus and the individual host. Influenza A viruses can also cause sporadic infections or spread worldwide in a pandemic when novel strains emerge in the human population from an animal host. New approaches to influenza prevention and treatment for management of both seasonal influenza epidemics and pandemics are desirable. In this Seminar, we discuss the clinical presentation, transmission, diagnosis, management, and prevention of seasonal influenza infection. We also review the animal-human interface of influenza, with a focus on current pandemic threats.
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Affiliation(s)
- Catharine Paules
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kanta Subbarao
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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5
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Gulati S, Lasanajak Y, Smith DF, Cummings RD, Air GM. Glycan array analysis of influenza H1N1 binding and release. Cancer Biomark 2015; 14:43-53. [PMID: 24643041 DOI: 10.3233/cbm-130376] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Influenza viruses initiate infection by attaching to sialic acid receptors on the surface of host cells. It has been recognized for some time that avian influenza viruses usually bind to terminal sialic acid that is linked in the α2-3 configuration to the next sugar while human viruses show preference for α2-6 linked sialic acid. With developments in synthetic chemistry and chemo-enzymatic methods of synthesizing quite complex glycans, it has become clear that the binding specificity extends beyond the sialic acid, and this has led to considerable interest in developing glycan reagents that could be used either as a diagnostic tool for particular influenza viruses, or to identify cells that are susceptible to infection by certain influenza viruses. Here we describe the use of the Consortium for Functional Glycomics Glycan Array to investigate binding specificity of influenza hemagglutinin and cleavage by neuraminidase, using seasonal and pandemic H1N1 influenza viruses as examples, and compare the results with published data using other array methods.
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Affiliation(s)
- Shelly Gulati
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, OK, USA
| | - Yi Lasanajak
- Department of Biochemistry, Emory University, OK, USA
| | - David F Smith
- Department of Biochemistry, Emory University, OK, USA
| | | | - Gillian M Air
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, OK, USA
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6
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Multiple influenza A (H3N2) mutations conferring resistance to neuraminidase inhibitors in a bone marrow transplant recipient. Antimicrob Agents Chemother 2014; 58:7188-97. [PMID: 25246391 DOI: 10.1128/aac.03667-14] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Immunocompromised patients are predisposed to infections caused by influenza virus. Influenza virus may produce considerable morbidity, including protracted illness and prolonged viral shedding in these patients, thus prompting higher doses and prolonged courses of antiviral therapy. This approach may promote the emergence of resistant strains. Characterization of neuraminidase (NA) inhibitor (NAI)-resistant strains of influenza A virus is essential for documenting causes of resistance. In this study, using quantitative real-time PCR along with conventional Sanger sequencing, we identified an NAI-resistant strain of influenza A (H3N2) virus in an immunocompromised patient. In-depth analysis by deep gene sequencing revealed that various known markers of antiviral resistance, including transient R292K and Q136K substitutions and a sustained E119K (N2 numbering) substitution in the NA protein emerged during prolonged antiviral therapy. In addition, a combination of a 4-amino-acid deletion at residues 245 to 248 (Δ245-248) accompanied by the E119V substitution occurred, causing resistance to or reduced inhibition by NAIs (oseltamivir, zanamivir, and peramivir). Resistant variants within a pool of viral quasispecies arose during combined antiviral treatment. More research is needed to understand the interplay of drug resistance mutations, viral fitness, and transmission.
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Abstract
It has been known for many years that influenza viruses bind by their hemagglutinin surface glycoprotein to sialic acid (N-acetylneuraminic acid) on the surface of the host cell, and that avian viruses most commonly bind to sialic acid linked α2-3 to galactose while most human viruses bind to sialic acid in the α2-6 configuration. Over the past few years there has been a large increase in data on this binding due to technological advances in glycan binding assays, reverse genetic systems for influenza and in X-ray crystallography. The results show some surprising changes in binding specificity that do not appear to affect the ability of the virus to infect host cells.
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Affiliation(s)
- Gillian M Air
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, 940 Stanton L. Young Blvd, Oklahoma City, OK 73104, USA.
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8
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Smith DF, Cummings RD. Investigating virus-glycan interactions using glycan microarrays. Curr Opin Virol 2014; 7:79-87. [PMID: 24995558 DOI: 10.1016/j.coviro.2014.05.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 05/27/2014] [Indexed: 01/01/2023]
Abstract
While all viruses must transit the plasma membrane of mammalian cells to initiate infection, we know little about the complex processes involved in viral attachment, which commonly involve recognition of glycans by viral proteins. Glycan microarrays derived from both synthetic glycans and natural glycans isolated through shotgun glycomics approaches provide novel platforms for interrogating diverse glycans as potential viral receptors. Recent studies with influenza and rotaviruses using such glycan microarrays provide examples of their utility in exploring the challenging questions raised in efforts to define the complex mechanistic protein-glycan interactions that regulate virus attachment to host cells.
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Affiliation(s)
- David F Smith
- The National Center for Functional Glycomics, Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Richard D Cummings
- The National Center for Functional Glycomics, Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, United States.
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9
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Paulson JC, de Vries RP. H5N1 receptor specificity as a factor in pandemic risk. Virus Res 2013; 178:99-113. [PMID: 23619279 PMCID: PMC3805702 DOI: 10.1016/j.virusres.2013.02.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 02/13/2013] [Accepted: 02/24/2013] [Indexed: 12/12/2022]
Abstract
The high pathogenicity of H5N1 viruses in sporadic infections of humans has raised concerns for its potential to acquire the ability to transmit between humans and emerge as a highly pathogenic pandemic virus. Because avian and human influenza viruses differ in their specificity for recognition of their host cell receptors, receptor specificity represents one barrier for efficient transmission of avian viruses in human hosts. Over the last century, each influenza virus pandemic has coincided with the emergence of virus with an immunologically distinct hemagglutinin exhibiting a 'human-type' receptor specificity, distinct from that of viruses with the same hemagglutinin circulating in zoonotic species. Recent studies suggest that it is possible for H5N1 to acquire human type receptor specificity, but this has not occurred in nature. This review covers what is known about the molecular basis for the switch between avian and human-type receptor specificity for influenza viruses that have successfully adapted to man, the potential for H5N1 to evolve to human-type receptor specificity and its relevance to pandemic risk.
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MESH Headings
- Animals
- Birds
- Hemagglutinin Glycoproteins, Influenza Virus/chemistry
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/metabolism
- Humans
- Influenza A Virus, H5N1 Subtype/chemistry
- Influenza A Virus, H5N1 Subtype/classification
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/metabolism
- Influenza in Birds/epidemiology
- Influenza in Birds/genetics
- Influenza in Birds/metabolism
- Influenza in Birds/virology
- Influenza, Human/epidemiology
- Influenza, Human/genetics
- Influenza, Human/metabolism
- Influenza, Human/virology
- Pandemics
- Receptors, Virus/genetics
- Receptors, Virus/metabolism
- Species Specificity
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Affiliation(s)
- James C Paulson
- Department of Chemical Physiology, The Scripps Research Institute, San Diego, CA 92037, USA.
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10
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Truncation and sequence shuffling of segment 6 generate replication-competent neuraminidase-negative influenza H5N1 viruses. J Virol 2013; 87:13556-68. [PMID: 24109212 DOI: 10.1128/jvi.02244-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Influenza viruses are highly genetically variable and escape from immunogenic pressure by antigenic changes in their surface proteins, referred to as "antigenic drift" and "antigenic shift." To assess the potential genetic plasticity under strong selection pressure, highly pathogenic avian influenza virus (HPAIV) of subtype H5N1 was passaged 50 times in embryonated chicken eggs in the presence of a neutralizing, polyclonal chicken serum. The resulting mutant acquired major alterations in the neuraminidase (NA)-encoding segment. Extensive deletions and rearrangements were detected, in contrast to only 12 amino acid substitutions within all other segments. Interestingly, this new neuraminidase segment resulted from complex sequence shuffling and insertion of a short fragment originating from the PA segment. Characterization of that novel variant revealed a loss of the neuraminidase protein and enzymatic activity, but its replication efficiency remained comparable to that of the wild type. Using reverse genetics, a recombinant virus consisting of the wild-type backbone and the shortened NA segment could be generated; however, generation of this recombinant virus required the polybasic hemagglutinin cleavage site. Two independent repetitions starting with egg passage 30 in the presence of alternative chicken-derived immune sera selected mutants with similar but different large deletions within the NA segment without any neuraminidase activity, indicating a general mechanism. In chicken, these virus variants were avirulent, even though the HPAIV polybasic hemagglutinin cleavage site was still present. Overall, the variants reported here are the first HPAIV H5N1 strains without a functional neuraminidase shown to grow efficiently without any helper factor. These novel HPAIV variants may facilitate future studies shedding light on the role of neuraminidase in virus replication and pathogenicity.
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11
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Gulati S, Smith DF, Cummings RD, Couch RB, Griesemer SB, St. George K, Webster RG, Air GM. Human H3N2 Influenza Viruses Isolated from 1968 To 2012 Show Varying Preference for Receptor Substructures with No Apparent Consequences for Disease or Spread. PLoS One 2013; 8:e66325. [PMID: 23805213 PMCID: PMC3689742 DOI: 10.1371/journal.pone.0066325] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 05/03/2013] [Indexed: 12/20/2022] Open
Abstract
It is generally accepted that human influenza viruses bind glycans containing sialic acid linked α2–6 to the next sugar, that avian influenza viruses bind glycans containing the α2–3 linkage, and that mutations that change the binding specificity might change the host tropism. We noted that human H3N2 viruses showed dramatic differences in their binding specificity, and so we embarked on a study of representative human H3N2 influenza viruses, isolated from 1968 to 2012, that had been isolated and minimally passaged only in mammalian cells, never in eggs. The 45 viruses were grown in MDCK cells, purified, fluorescently labeled and screened on the Consortium for Functional Glycomics Glycan Array. Viruses isolated in the same season have similar binding specificity profiles but the profiles show marked year-to-year variation. None of the 610 glycans on the array (166 sialylated glycans) bound to all viruses; the closest was Neu5Acα2–6(Galβ1–4GlcNAc)3 in either a linear or biantennary form, that bound 42 of the 45 viruses. The earliest human H3N2 viruses preferentially bound short, branched sialylated glycans while recent viruses bind better to long polylactosamine chains terminating in sialic acid. Viruses isolated in 1996, 2006, 2010 and 2012 bind glycans with α2–3 linked sialic acid; for 2006, 2010 and 2012 viruses this binding was inhibited by oseltamivir, indicating binding of α2–3 sialylated glycans by neuraminidase. More significantly, oseltamivir inhibited virus entry of 2010 and 2012 viruses into MDCK cells. All of these viruses were representative of epidemic strains that spread around the world, so all could infect and transmit between humans with high efficiency. We conclude that the year-to-year variation in receptor binding specificity is a consequence of amino acid sequence changes driven by antigenic drift, and that viruses with quite different binding specificity and avidity are equally fit to infect and transmit in the human population.
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Affiliation(s)
- Shelly Gulati
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - David F. Smith
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Richard D. Cummings
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Robert B. Couch
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Sara B. Griesemer
- New York State Department of Health, Wadsworth Center, Albany, New York, United States of America
| | - Kirsten St. George
- New York State Department of Health, Wadsworth Center, Albany, New York, United States of America
| | - Robert G. Webster
- St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Gillian M. Air
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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Hobbie SN, Viswanathan K, Bachelet I, Aich U, Shriver Z, Subramanian V, Raman R, Sasisekharan R. Modular glycosphere assays for high-throughput functional characterization of influenza viruses. BMC Biotechnol 2013; 13:34. [PMID: 23587408 PMCID: PMC3751502 DOI: 10.1186/1472-6750-13-34] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 03/18/2013] [Indexed: 11/16/2022] Open
Abstract
Background The ongoing global efforts to control influenza epidemics and pandemics require high-throughput technologies to detect, quantify, and functionally characterize viral isolates. The 2009 influenza pandemic as well as the recent in-vitro selection of highly transmissible H5N1 variants have only increased existing concerns about emerging influenza strains with significantly enhanced human-to-human transmissibility. High-affinity binding of the virus hemagglutinin to human receptor glycans is a highly sensitive and stringent indicator of host adaptation and virus transmissibility. The surveillance of receptor-binding characteristics can therefore provide a strong additional indicator for the relative hazard imposed by circulating and newly emerging influenza strains. Results Streptavidin-coated microspheres were coated with selected biotinylated glycans to mimic either human or avian influenza host-cell receptors. Such glycospheres were used to selectively capture influenza virus of diverse subtypes from a variety of samples. Bound virus was then detected by fluorescently labelled antibodies and analyzed by quantitative flow cytometry. Recombinant hemagglutinin, inactivated virus, and influenza virions were captured and analyzed with regards to receptor specificity over a wide range of analyte concentration. High-throughput analyses of influenza virus produced dose–response curves that allow for functional assessment of relative receptor affinity and thus transmissibility. Conclusions Modular glycosphere assays for high-throughput functional characterization of influenza viruses introduce an important tool to augment the surveillance of clinical and veterinarian influenza isolates with regards to receptor specificity, host adaptation, and virus transmissibility.
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Affiliation(s)
- Sven N Hobbie
- Singapore-MIT Alliance for Research and Technology, Singapore 138602, Singapore
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13
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Walther T, Karamanska R, Chan RWY, Chan MCW, Jia N, Air G, Hopton C, Wong MP, Dell A, Malik Peiris JS, Haslam SM, Nicholls JM. Glycomic analysis of human respiratory tract tissues and correlation with influenza virus infection. PLoS Pathog 2013; 9:e1003223. [PMID: 23516363 PMCID: PMC3597497 DOI: 10.1371/journal.ppat.1003223] [Citation(s) in RCA: 195] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 01/16/2013] [Indexed: 11/19/2022] Open
Abstract
The first step in influenza infection of the human respiratory tract is binding of the virus to sialic (Sia) acid terminated receptors. The binding of different strains of virus for the receptor is determined by the α linkage of the sialic acid to galactose and the adjacent glycan structure. In this study the N- and O-glycan composition of the human lung, bronchus and nasopharynx was characterized by mass spectrometry. Analysis showed that there was a wide spectrum of both Sia α2-3 and α2-6 glycans in the lung and bronchus. This glycan structural data was then utilized in combination with binding data from 4 of the published glycan arrays to assess whether these current glycan arrays were able to predict replication of human, avian and swine viruses in human ex vivo respiratory tract tissues. The most comprehensive array from the Consortium for Functional Glycomics contained the greatest diversity of sialylated glycans, but was not predictive of productive replication in the bronchus and lung. Our findings indicate that more comprehensive but focused arrays need to be developed to investigate influenza virus binding in an assessment of newly emerging influenza viruses. This study was performed to determine what possible glycan receptors for influenza were present in the human respiratory tract. We compared the glycans present on existing published glycan arrays with the actual glycans identified in the human respiratory tract by mass spectrometric analysis to determine how representative these arrays would be for potential binding. The most comprehensive array to date only contained approximately half the range of the actual glycans present. Over the past 5 years we have performed ex-vivo infection of 113 bronchial and 185 lung samples with seasonal, avian and swine influenza viruses, and have demonstrated that the lung is able to be infected by all types of influenza viruses but that the bronchus can also be infected by a limited range of avian, swine and seasonal viruses. The key findings are that there is wide spectrum of glycans present in the respiratory tract which can be used by influenza viruses for infection, and the currently available arrays are not predictive of successful infection. Our findings will be of use for researchers in developing more comprehensive and focused arrays for the screening of emerging influenza viruses and bacteria in order to determine their potential threat to humans.
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Affiliation(s)
- Trevenan Walther
- Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
| | - Rositsa Karamanska
- Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Renee W. Y. Chan
- Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
- Centre of Influenza Research, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Michael C. W. Chan
- Centre of Influenza Research, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Nan Jia
- Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Gillian Air
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Clark Hopton
- Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
| | - Maria P. Wong
- Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
| | - Anne Dell
- Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London, United Kingdom
| | - J. S. Malik Peiris
- Centre of Influenza Research, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
- HKU-Pasteur Research Centre, Hong Kong, China
| | - Stuart M. Haslam
- Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London, United Kingdom
- * E-mail: .
| | - John M. Nicholls
- Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
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14
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Galloway SE, Reed ML, Russell CJ, Steinhauer DA. Influenza HA subtypes demonstrate divergent phenotypes for cleavage activation and pH of fusion: implications for host range and adaptation. PLoS Pathog 2013; 9:e1003151. [PMID: 23459660 PMCID: PMC3573126 DOI: 10.1371/journal.ppat.1003151] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 12/07/2012] [Indexed: 12/17/2022] Open
Abstract
The influenza A virus (IAV) HA protein must be activated by host cells proteases in order to prime the molecule for fusion. Consequently, the availability of activating proteases and the susceptibility of HA to protease activity represents key factors in facilitating virus infection. As such, understanding the intricacies of HA cleavage by various proteases is necessary to derive insights into the emergence of pandemic viruses. To examine these properties, we generated a panel of HAs that are representative of the 16 HA subtypes that circulate in aquatic birds, as well as HAs representative of the subtypes that have infected the human population over the last century. We examined the susceptibility of the panel of HA proteins to trypsin, as well as human airway trypsin-like protease (HAT) and transmembrane protease, serine 2 (TMPRSS2). Additionally, we examined the pH at which these HAs mediated membrane fusion, as this property is related to the stability of the HA molecule and influences the capacity of influenza viruses to remain infectious in natural environments. Our results show that cleavage efficiency can vary significantly for individual HAs, depending on the protease, and that some HA subtypes display stringent selectivity for specific proteases as activators of fusion function. Additionally, we found that the pH of fusion varies by 0.7 pH units among the subtypes, and notably, we observed that the pH of fusion for most HAs from human isolates was lower than that observed from avian isolates of the same subtype. Overall, these data provide the first broad-spectrum analysis of cleavage-activation and membrane fusion characteristics for all of the IAV HA subtypes, and also show that there are substantial differences between the subtypes that may influence transmission among hosts and establishment in new species. IAV is associated with significant morbidity and mortality, and represents a challenging public health threat that affects social and economic welfare each year, particularly during IAV pandemics. Although we know that all human strains derive, either directly or via intermediate hosts, from avian viral sources, we know very little about the phenotypic characteristics of the 16 HA subtypes that circulate in aquatic birds and have potential to infect mammals. HA membrane fusion properties, in conjunction with the characteristics for protease activation of HA, a requirement for fusion, are critical factors involved in the ecology and transmission of IAVs, and need to be understood if we are to derive explanations for how pandemic viruses emerge in humans. We examined the cleavage-activation and membrane fusion characteristics for the 16 HA subtypes by transiently expressing HA proteins in cells. Our findings show that the cleavability of the HAs vary considerably between subtypes and depending on the protease. Additionally, analysis of the pH of fusion for each subtype showed that HA stability varied significantly among the subtypes, as well as within subtypes from viruses isolated from different species. Overall, these data have implications for host range, potential for adaptation, and persistence in natural environments.
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Affiliation(s)
- Summer E. Galloway
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail: (SEG); (DAS)
| | - Mark L. Reed
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Charles J. Russell
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - David A. Steinhauer
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail: (SEG); (DAS)
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15
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Iqbal M, Essen SC, Xiao H, Brookes SM, Brown IH, McCauley JW. Selection of variant viruses during replication and transmission of H7N1 viruses in chickens and turkeys. Virology 2012; 433:282-95. [PMID: 22944111 DOI: 10.1016/j.virol.2012.08.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 05/25/2012] [Accepted: 08/01/2012] [Indexed: 02/06/2023]
Abstract
The influence of different glycosylation patterns of the haemagglutinin glycoprotein of H7N1 avian influenza viruses on virus replication in vivo was examined. Experimental infection of chickens and turkeys was carried out with H7N1 avian influenza viruses with alternative sites of glycosylation in the haemagglutinin and infected birds were sampled daily by swabbing the buccal and cloacal cavities. cDNAs of the HA1 coding region of the HA gene were prepared from the swabs and cloned into plasmids. Sequencing multiple plasmids made from individual swabs taken over the period of virus shedding showed that viruses with specific patterns of glycosylation near the receptor binding site were stable when birds were infected with a single variant, but when presented with a mixed population of viruses encoding differing patterns of glycosylation a specific variant was rapidly selected in the infected host.
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MESH Headings
- Animals
- Asparagine/chemistry
- Chickens/virology
- Genes, Viral
- Genetic Variation
- Glycosylation
- Hemagglutinin Glycoproteins, Influenza Virus/chemistry
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Influenza A Virus, H7N1 Subtype/genetics
- Influenza A Virus, H7N1 Subtype/isolation & purification
- Influenza A Virus, H7N1 Subtype/pathogenicity
- Influenza A Virus, H7N1 Subtype/physiology
- Italy
- Models, Molecular
- Protein Conformation
- RNA, Viral/genetics
- RNA, Viral/isolation & purification
- Selection, Genetic
- Turkeys/virology
- Virus Replication
- Virus Shedding
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Affiliation(s)
- Munir Iqbal
- Avian Viral Diseases Programme, Institute for Animal Health, Compton Laboratory, Compton, Newbury, Berkshire RG20 7NN, UK.
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16
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Entry of influenza A Virus with a α2,6-linked sialic acid binding preference requires host fibronectin. J Virol 2012; 86:10704-13. [PMID: 22837202 DOI: 10.1128/jvi.01166-12] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The receptor binding specificity of influenza A virus is one of the major determinants of viral tropism and host specificity. In general, avian viral hemagglutinin prefers to bind to α2,3-linked sialic acid, whereas the human viral hemagglutinin prefers to bind to α2,6-linked sialic acid. Here, we demonstrate that host fibronectin protein plays an important role in the life cycle of some influenza A viruses. Treating cells with anti-fibronectin antibodies or fibronectin-specific small interfering RNA can inhibit the virus replication of human H1N1 influenza A viruses. Strikingly, these inhibitory effects cannot be observed in cells infected with H5N1 viruses. By using reverse genetics techniques, we observed that the receptor binding specificity, but not the origin of the hemagglutinin subtype, is responsible for this differential inhibitory effect. Changing the binding preference of hemagglutinin from α2,6-linked sialic acid to α2,3-linked sialic acid can make the virus resistant to the anti-fibronectin antibody treatment and vice versa. Our further characterizations indicate that anti-fibronectin antibody acts on the early phase of viral replication cycle, but it has no effect on the initial binding of influenza A virus to cell surface. Our subsequent investigations further show that anti-fibronectin antibody can block the postattachment entry of influenza virus. Overall, these results indicate that the sialic acid binding preference of influenza viral hemagglutinin can modulate the preferences of viral entry pathways, suggesting that there are subtle differences between the virus entries of human and avian influenza viruses.
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17
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Abstract
Influenza neuraminidase is the target of two licensed antivirals that have been very successful, with several more in development. However, neuraminidase has been largely ignored as a vaccine target despite evidence that inclusion of neuraminidase in the subunit vaccine gives increased protection. This article describes current knowledge on the structure, enzyme activity, and antigenic significance of neuraminidase.
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Affiliation(s)
- Gillian M Air
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
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18
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Stray SJ, Pittman LB. Subtype- and antigenic site-specific differences in biophysical influences on evolution of influenza virus hemagglutinin. Virol J 2012; 9:91. [PMID: 22569196 PMCID: PMC3499391 DOI: 10.1186/1743-422x-9-91] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 04/10/2012] [Indexed: 11/14/2022] Open
Abstract
Background Influenza virus undergoes rapid evolution by both antigenic shift and antigenic drift. Antibodies, particularly those binding near the receptor-binding site of hemagglutinin (HA) or the neuraminidase (NA) active site, are thought to be the primary defense against influenza infection, and mutations in antibody binding sites can reduce or eliminate antibody binding. The binding of antibodies to their cognate antigens is governed by such biophysical properties of the interacting surfaces as shape, non-polar and polar surface area, and charge. Methods To understand forces shaping evolution of influenza virus, we have examined HA sequences of human influenza A and B viruses, assigning each amino acid values reflecting total accessible surface area, non-polar and polar surface area, and net charge due to the side chain. Changes in each of these values between neighboring sequences were calculated for each residue and mapped onto the crystal structures. Results Areas of HA showing the highest frequency of pairwise changes agreed well with previously identified antigenic sites in H3 and H1 HAs, and allowed us to propose more detailed antigenic maps and novel antigenic sites for H1 and influenza B HA. Changes in biophysical properties differed between HAs of different subtypes, and between different antigenic sites of the same HA. For H1, statistically significant differences in several biophysical quantities compared to residues lying outside antigenic sites were seen for some antigenic sites but not others. Influenza B antigenic sites all show statistically significant differences in biophysical quantities for all antigenic sites, whereas no statistically significant differences in biophysical quantities were seen for any antigenic site is seen for H3. In many cases, residues previously shown to be under positive selection at the genetic level also undergo rapid change in biophysical properties. Conclusions The biophysical consequences of amino acid changes introduced by antigenic drift vary from subtype to subtype, and between different antigenic sites. This suggests that the significance of antibody binding in selecting new variants may also be variable for different antigenic sites and influenza subtypes.
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Affiliation(s)
- Stephen J Stray
- Department of Microbiology, University of Mississippi Medical Center, 2500 N State St, Jackson, MS 39216, USA.
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19
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Bateman AC, Busch MG, Karasin AI, Olsen CW. Infectivity phenotypes of H3N2 influenza A viruses in primary swine respiratory epithelial cells are controlled by sialic acid binding. Influenza Other Respir Viruses 2012; 6:424-33. [PMID: 22353399 DOI: 10.1111/j.1750-2659.2012.00333.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND In the late 1990s, triple reassortant H3N2 influenza A viruses emerged and spread widely in the US swine population. We have shown previously that an isolate representative of this virus-lineage, A/Swine/Minnesota/593/99 (Sw/MN), exhibits phenotypic differences compared to a wholly human-lineage H3N2 virus isolated during the same time period, A/Swine/Ontario/00130/97 (Sw/ONT). Specifically, Sw/MN was more infectious for pigs and infected a significantly higher proportion of cultured primary swine respiratory epithelial cells (SRECs). In addition, reverse genetics-generated Sw/MN × Sw/ONT reassortant and point mutant viruses demonstrated that the infectivity phenotypes in SRECs were strongly dependent on three amino acids within the hemagglutinin (HA) gene. OBJECTIVES To determine the mechanism by which Sw/MN attains higher infectivity than Sw/ONT in SRECs. METHODS A/Swine/Minnesota/593/99, Sw/ONT, and mutant (reverse genetics-generated HA reassortant and point mutant) viruses were compared at various HA-mediated stages of infection: initial sialic acid binding, virus entry, and the pH of virus-endosome fusion. RESULTS/CONCLUSIONS Sialic acid binding was the sole stage where virus differences directly paralleled infectivity phenotypes in SRECs, indicating that binding is the primary mechanism responsible for differences in the infectivity levels of Sw/MN and Sw/ONT.
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Affiliation(s)
- Allen C Bateman
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
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20
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Heimburg-Molinaro J, Tappert M, Song X, Lasanajak Y, Air G, Smith DF, Cummings RD. Probing virus-glycan interactions using glycan microarrays. Methods Mol Biol 2012; 808:251-67. [PMID: 22057531 DOI: 10.1007/978-1-61779-373-8_18] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Glycan microarrays are surfaces that contain immobilized oligosaccharides or glycoconjugates and have proven useful in probing the interactions between glycan-binding proteins (GBPs) and individual glycans. Such glycan microarrays have been especially important in studying virus-glycan interactions, as most viruses express one or more GBPs important for pathogenesis. For studying interactions of influenza viruses with glycans, we describe protocols for fluorescent labeling of virus, addition of virus to a glycan microarray, analysis of a glycan microarray slide experiment, and interpretation of data.
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Affiliation(s)
- Jamie Heimburg-Molinaro
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
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21
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Air GM, Feng J, Chen T, Joachims ML, James JA, Thompson LF. Individual antibody and T cell responses to vaccination and infection with the 2009 pandemic swine-origin H1N1 influenza virus. J Clin Immunol 2011; 31:900-12. [PMID: 21732013 PMCID: PMC3197711 DOI: 10.1007/s10875-011-9563-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 06/22/2011] [Indexed: 10/18/2022]
Abstract
INTRODUCTION The 2009 swine-origin H1N1 influenza virus (swH1N1) provided an opportunity to study immune responses to a new influenza strain in the context of seasonal influenza vaccination. Our goals were: to assess whether analyzing multiple parameters of immune responsiveness to influenza has an advantage over evaluating hemagglutination inhibition (HAI) titer alone, to determine whether vaccination with the seasonal vaccine induced cross-reactive immunity to swH1N1 in some individuals, and to determine whether the immune response against swH1N1 is higher after infection than vaccination. METHODS Antibody and T cell responses were studied in ten subjects who were first immunized with the 2009-2010 seasonal influenza subunit vaccine, then 6 weeks later with the swH1N1 monovalent subunit vaccine. The amount of antibody against native virus glycoproteins, overall avidity of these antibodies, and HAI titer were measured. T cells were evaluated for proliferation and IFNγ secretion in response to the vaccine in vitro. Individuals with influenza-like illness were also evaluated, adding a microplate neuraminidase inhibition (NAI) test. RESULTS The immune response to influenza was highly variable and immune parameters did not increase in parallel. The seasonal vaccine induced antibodies recognizing the pandemic virus in 50% of subjects. Antibody affinity and NAI activity to swH1N1 were higher after natural infection than vaccination. CONCLUSIONS The evaluation of several immune parameters gives a more complete measure of immune responsiveness to influenza infection or vaccination than the HAI test alone.
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MESH Headings
- Animals
- Antibodies, Viral/blood
- Antibodies, Viral/immunology
- Antigens, Viral/immunology
- Cells, Cultured
- Cross Reactions
- Hemagglutination Inhibition Tests/methods
- Humans
- Influenza A Virus, H1N1 Subtype/immunology
- Influenza A Virus, H1N1 Subtype/pathogenicity
- Influenza Vaccines
- Influenza, Human/diagnosis
- Influenza, Human/epidemiology
- Influenza, Human/immunology
- Influenza, Human/physiopathology
- Monitoring, Immunologic/methods
- Pandemics
- Swine
- T-Lymphocytes/immunology
- T-Lymphocytes/virology
- United States
- Vaccination
- Zoonoses
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Affiliation(s)
- Gillian M. Air
- University of Oklahoma Health Sciences Center, Department of Biochemistry and Molecular Biology, Oklahoma City, Oklahoma, United States
| | - JingQi Feng
- University of Oklahoma Health Sciences Center, Department of Biochemistry and Molecular Biology, Oklahoma City, Oklahoma, United States
| | - Tao Chen
- University of Oklahoma Health Sciences Center, Department of Biochemistry and Molecular Biology, Oklahoma City, Oklahoma, United States
| | - Michelle L. Joachims
- Oklahoma Medical Research Foundation, Immunobiology and Cancer Program, Oklahoma City, Oklahoma, United States
| | - Judith A. James
- Oklahoma Medical Research Foundation, Arthritis and Clinical Immunology Program, Oklahoma City, Oklahoma, United States
| | - Linda F. Thompson
- Oklahoma Medical Research Foundation, Immunobiology and Cancer Program, Oklahoma City, Oklahoma, United States
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22
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Song X, Yu H, Chen X, Lasanajak Y, Tappert MM, Air GM, Tiwari VK, Cao H, Chokhawala HA, Zheng H, Cummings RD, Smith DF. A sialylated glycan microarray reveals novel interactions of modified sialic acids with proteins and viruses. J Biol Chem 2011; 286:31610-22. [PMID: 21757734 PMCID: PMC3173124 DOI: 10.1074/jbc.m111.274217] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 07/07/2011] [Indexed: 01/22/2023] Open
Abstract
Many glycan-binding proteins in animals and pathogens recognize sialic acid or its modified forms, but their molecular recognition is poorly understood. Here we describe studies on sialic acid recognition using a novel sialylated glycan microarray containing modified sialic acids presented on different glycan backbones. Glycans terminating in β-linked galactose at the non-reducing end and with an alkylamine-containing fluorophore at the reducing end were sialylated by a one-pot three-enzyme system to generate α2-3- and α2-6-linked sialyl glycans with 16 modified sialic acids. The resulting 77 sialyl glycans were purified and quantified, characterized by mass spectrometry, covalently printed on activated slides, and interrogated with a number of key sialic acid-binding proteins and viruses. Sialic acid recognition by the sialic acid-binding lectins Sambucus nigra agglutinin and Maackia amurensis lectin-I, which are routinely used for detecting α2-6- and α2-3-linked sialic acids, are affected by sialic acid modifications, and both lectins bind glycans terminating with 2-keto-3-deoxy-D-glycero-D-galactonononic acid (Kdn) and Kdn derivatives stronger than the derivatives of more common N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc). Three human parainfluenza viruses bind to glycans terminating with Neu5Ac or Neu5Gc and some of their derivatives but not to Kdn and its derivatives. Influenza A virus also does not bind glycans terminating in Kdn or Kdn derivatives. An especially novel aspect of human influenza A virus binding is its ability to equivalently recognize glycans terminated with either α2-6-linked Neu5Ac9Lt or α2-6-linked Neu5Ac. Our results demonstrate the utility of this sialylated glycan microarray to investigate the biological importance of modified sialic acids in protein-glycan interactions.
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Affiliation(s)
- Xuezheng Song
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Hai Yu
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Xi Chen
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Yi Lasanajak
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Mary M. Tappert
- the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73126
| | - Gillian M. Air
- the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73126
| | - Vinod K. Tiwari
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Hongzhi Cao
- the Department of Chemistry, University of California, Davis, California 95616, and
| | | | - Haojie Zheng
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Richard D. Cummings
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
| | - David F. Smith
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
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23
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Thangavel RR, Reed A, Norcross EW, Dixon SN, Marquart ME, Stray SJ. "Boom" and "Bust" cycles in virus growth suggest multiple selective forces in influenza a evolution. Virol J 2011; 8:180. [PMID: 21501520 PMCID: PMC3339368 DOI: 10.1186/1743-422x-8-180] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 04/18/2011] [Indexed: 11/28/2022] Open
Abstract
Background Influenza A virus evolution in humans is driven at least in part by mutations allowing the virus to escape antibody neutralization. Little is known about the evolution of influenza in birds, a major reservoir of influenza A. Methods Neutralizing polyclonal antiserum was raised in chicken against reassortant influenza virus, CalX, bearing the hemagglutinin (HA) and neuraminidase (NA) of A/California/7/2004 [H3N2]. CalX was serially passaged in the presence of anti-CalX polyclonal IgY to derive viruses capable of growth in the presence of antibody. Results Polyclonal chicken antibody neutralized both HA activity and infection by CalX, but had no effect on a strain bearing an earlier human H3 and an irrelevant neuraminidase (A/Memphis/71-Bellamy/42 [H3N1]). Surprisingly, most of the antibody-resistant viruses were still at least partially sensitive to neutralization of HA activity and viral infection. Although mutant HA genes bearing changes that might affect antibody neutralization were identified, the vast majority of HA sequences obtained were identical to wild type, and no individual mutant sequence was found in more than one passage, suggesting that those mutations that were observed did not confer sufficient selective advantage to come to dominate the population. Different passages yielded infectious foci of varying size and plaques of varying size and morphology. Yields of infectious virus and relative frequency of different morphologies changed markedly from passage to passage. Sequences of bulk, uncloned PCR products from antibody-resistant passages indicated changes in the PB2 and PA proteins with respect to the wild type virus. Conclusions Each antibody-selected passage consisted of a variety of different cocirculating populations, rather than pure populations of virus able to escape antibody by changes in antibody epitopes. The ability to escape antibody is apparently due to changes in genes encoding the viral polymerase complex, probably resulting in more robust viral replication, allowing the few virus particles not completely neutralized by antibody to rapidly produce large numbers of progeny. Our data suggest that the relative success of an individual variant may depend on both its own gain and loss of fitness, as well as that of its cocirculating variants.
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Affiliation(s)
- Rajagowthamee R Thangavel
- Department of Microbiology, University of Mississippi Medical Center, 2500 N State St, Jackson, MS 39216, USA
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24
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Bateman AC, Karamanska R, Busch MG, Dell A, Olsen CW, Haslam SM. Glycan analysis and influenza A virus infection of primary swine respiratory epithelial cells: the importance of NeuAc{alpha}2-6 glycans. J Biol Chem 2010; 285:34016-26. [PMID: 20724471 PMCID: PMC2962501 DOI: 10.1074/jbc.m110.115998] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 08/18/2010] [Indexed: 12/16/2022] Open
Abstract
To better understand influenza virus infection of pigs, we examined primary swine respiratory epithelial cells (SRECs, the primary target cells of influenza viruses in vivo), as a model system. Glycomic profiling of SRECs by mass spectrometry revealed a diverse range of glycans terminating in sialic acid or GalαGal. In terms of sialylation, α2-6 linkage was more abundant than α2-3, and NeuAc was more abundant than NeuGc. Virus binding and infection experiments were conducted to determine functionally important glycans for influenza virus infection, with a focus on recently emerged swine viruses. Infection of SRECs with swine and human viruses resulted in different infectivity levels. Glycan microarray analysis with a high infectivity "triple reassortant" virus ((A/Swine/MN/593/99 (H3N2)) that spread widely throughout the North American swine population and a lower infectivity human virus isolated from a single pig (A/Swine/ONT/00130/97 (H3N2)) showed that both viruses bound exclusively to glycans containing NeuAcα2-6, with strong binding to sialylated polylactosamine and sialylated N-glycans. Treatment with mannosamine precursors of sialic acid (to alter NeuAc/NeuGc abundances) and linkage-specific sialidases prior to infection indicated that the influenza viruses tested preferentially utilize NeuAcα2-6-sialylated glycans to infect SRECs. Our data indicate that NeuAcα2-6-terminated polylactosamine and sialylated N-glycans are important determinants for influenza viruses to infect SRECs. As NeuAcα2-6 polylactosamine glycans play major roles in human virus infection, the importance of these receptor components in virus infection of swine cells has implications for transmission of viruses between humans and pigs and for pigs as possible adaptation hosts of novel human influenza viruses.
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Affiliation(s)
- Allen C. Bateman
- From the Department of Pathobiological Sciences, School of Veterinary Medicine, and
- Cellular and Molecular Biology Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin 53706 and
| | - Rositsa Karamanska
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Marc G. Busch
- From the Department of Pathobiological Sciences, School of Veterinary Medicine, and
| | - Anne Dell
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Christopher W. Olsen
- From the Department of Pathobiological Sciences, School of Veterinary Medicine, and
| | - Stuart M. Haslam
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Biochemistry Building, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
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25
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Stevens J, Chen LM, Carney PJ, Garten R, Foust A, Le J, Pokorny BA, Manojkumar R, Silverman J, Devis R, Rhea K, Xu X, Bucher DJ, Paulson J, Cox NJ, Klimov A, Donis RO. Receptor specificity of influenza A H3N2 viruses isolated in mammalian cells and embryonated chicken eggs. J Virol 2010; 84:8287-99. [PMID: 20519409 PMCID: PMC2916524 DOI: 10.1128/jvi.00058-10] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 05/18/2010] [Indexed: 11/20/2022] Open
Abstract
Isolation of human subtype H3N2 influenza viruses in embryonated chicken eggs yields viruses with amino acid substitutions in the hemagglutinin (HA) that often affect binding to sialic acid receptors. We used a glycan array approach to analyze the repertoire of sialylated glycans recognized by viruses from the same clinical specimen isolated in eggs or cell cultures. The binding profiles of whole virions to 85 sialoglycans on the microarray allowed the categorization of cell isolates into two groups. Group 1 cell isolates displayed binding to a restricted set of alpha2-6 and alpha2-3 sialoglycans, whereas group 2 cell isolates revealed receptor specificity broader than that of their egg counterparts. Egg isolates from group 1 showed binding specificities similar to those of cell isolates, whereas group 2 egg isolates showed a significantly reduced binding to alpha2-6- and alpha2-3-type receptors but retained substantial binding to specific O- and N-linked alpha2-3 glycans, including alpha2-3GalNAc and fucosylated alpha2-3 glycans (including sialyl Lewis x), both of which may be important receptors for H3N2 virus replication in eggs. These results revealed an unexpected diversity in receptor binding specificities among recent H3N2 viruses, with distinct patterns of amino acid substitution in the HA occurring upon isolation and/or propagation in eggs. These findings also suggest that clinical specimens containing viruses with group 1-like receptor binding profiles would be less prone to undergoing receptor binding or antigenic changes upon isolation in eggs. Screening cell isolates for appropriate receptor binding properties might help focus efforts to isolate the most suitable viruses in eggs for production of antigenically well-matched influenza vaccines.
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Affiliation(s)
- James Stevens
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Li-Mei Chen
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Paul J. Carney
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Rebecca Garten
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Angie Foust
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Jianhua Le
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Barbara A. Pokorny
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Ramanunninair Manojkumar
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Jeanmarie Silverman
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Rene Devis
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Karen Rhea
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Xiyan Xu
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Doris J. Bucher
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - James Paulson
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Nancy J. Cox
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Alexander Klimov
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
| | - Ruben O. Donis
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, Departments of Chemical Physiology and Molecular Biology, The Scripps Research Institute, La Jolla, California
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Li J, Cardona CJ. Adaptation and transmission of a wild duck avian influenza isolate in chickens. Avian Dis 2010; 54:586-90. [PMID: 20521699 DOI: 10.1637/8806-040109-resnote.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mutations in a wild duck isolate of avian influenza virus were detected in isolates shed by chickens within 1 day after inoculation. The newly adapted virus was transmitted to naïve chickens in direct contact and sharing food and water. Two consistent amino acid substitutions in the hemagglutinin have been identified, A198V and S274F, and may be important in transmissibility. Mutants with a 30-amino acid deletion in the neuraminidase stalk region 43-72 (N9 numbering) were recovered from inoculated chickens, but not from naïve chickens in contact. The NA stalk mutant virus did not replicate well in Pekin ducks. In vivo viral replication was at low titers and a change in tropism from the respiratory to the digestive tract was observed. Our results indicated that there is a rapid genetic adaptation of wild bird isolates in poultry species, but that resultant viruses may have phenotypes that are intermediate and not fully adapted to the new host.
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Affiliation(s)
- Jinling Li
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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27
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Mochalova L, Bright R, Xu X, Korchagina E, Chinarev A, Bovin N, Klimov A. Shift in oligosaccharide specificities of hemagglutinin and neuraminidase of influenza B viruses resistant to neuraminidase inhibitors. Glycoconj J 2010; 27:321-7. [PMID: 20195900 DOI: 10.1007/s10719-010-9280-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 01/07/2010] [Accepted: 02/02/2010] [Indexed: 11/28/2022]
Abstract
Influenza virus neuraminidase inhibitors (NAIs), currently used as anti-influenza drugs, can lead to the appearance of drug-resistant variants. Resistance to NAIs appears due to mutations in the active site of the neuraminidase (NA) molecule that decrease the NA enzymatic activity and sometimes in the hemagglutinin (HA) that decrease its affinity for cell receptors and, therefore, reduce the requirement for NA activity in releasing mature virions from infected cells. Using a set of sialo-oligosaccharides, we evaluated changes in the receptor-binding specificity of the HA and substrate specificity of the NA of influenza B viruses that had acquired resistance to NAIs. The oligosaccharide specificity of two pairs of field influenza B viruses, namely: i) B/Memphis/20/96 and its NAI-resistant variant, B/Memphis/20-152K/96, containing mutation R152K in the NA and 5 amino acid substitutions in the HA1, and ii) B/Hong Kong/45/2005 and its NAI-resistant variant B/Hong Kong/36/2005, containing a single R371K mutation in the NA, was evaluated. Wild type viruses bound strictly to a "human type" receptor, alpha2-6-sialo-oligosaccharide 6;SLN, but desialylated it is approximately 8 times less efficiently than the alpha2-3 sialosaccharides. Both drug-resistant viruses demonstrated the ability to bind to "avian type" receptors, alpha2-3 sialo-oligosaccharides (such as 3;SLN), whereas their affinity for 6;SLN was noticeably reduced in comparison with corresponding wild type viruses. Thus, the development of the NAI resistance in the studied influenza B viruses was accompanied by a readjustment of HA-NA oligosaccharide specificities.
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Affiliation(s)
- Larisa Mochalova
- Russian Academy of Sciences, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Miklukho-Maklaya 16/10, Moscow, 117997, Russia.
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28
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Feng J, Gulati U, Zhang X, Keitel WA, Thompson DM, James JA, Thompson LF, Air GM. Antibody quantity versus quality after influenza vaccination. Vaccine 2009; 27:6358-62. [PMID: 19840673 PMCID: PMC2765411 DOI: 10.1016/j.vaccine.2009.06.090] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 06/15/2009] [Accepted: 06/29/2009] [Indexed: 11/26/2022]
Abstract
The correlates for protection against influenza infection are incompletely characterized. We have applied an ELISA strategy that distinguishes antibodies against native viral surface antigens (potentially neutralizing) from antibodies directed against internal and denatured viral proteins (not neutralizing) to three groups of vaccinated subjects: (1) participants in a study of repeated annual vaccination, (2) elderly subjects and (3) patients with Systemic Lupus Erythematosus compared to control subjects. Antibody increase after vaccination was inversely related to the level of pre-existing antibodies in all groups; most subjects had significant initial antibody levels and showed little increase in amount of antibody after vaccination, but the avidity of their serum antibodies tended to increase. Antibodies against denatured virus proteins varied with vaccine formulation; vaccines that are more recent have less total protein for the same amount of native hemagglutinin. We propose an index consisting of rank order of antibody level plus antibody avidity, both measured against native virus, plus hemagglutination-inhibition antibody titer, as a useful measure of immunity against influenza.
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Affiliation(s)
- JingQi Feng
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126-0901, USA
| | - Upma Gulati
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126-0901, USA
| | - Xiaoju Zhang
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126-0901, USA
| | | | - David M. Thompson
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126-0901, USA
| | - Judith A. James
- Oklahoma Medical Research Foundation, 825 NE 13 Street, Oklahoma City, OK 73104, USA
| | - Linda F. Thompson
- Oklahoma Medical Research Foundation, 825 NE 13 Street, Oklahoma City, OK 73104, USA
| | - Gillian M. Air
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126-0901, USA
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29
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Arya SC, Agarwal N. Apropos “Vaccines in a hurry”. Vaccine 2009; 27:4875. [DOI: 10.1016/j.vaccine.2009.06.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 06/07/2009] [Indexed: 10/20/2022]
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30
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Cummings RD. The repertoire of glycan determinants in the human glycome. MOLECULAR BIOSYSTEMS 2009; 5:1087-104. [PMID: 19756298 DOI: 10.1039/b907931a] [Citation(s) in RCA: 361] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The number of glycan determinants that comprise the human glycome is not known. This uncertainty arises from limited knowledge of the total number of distinct glycans and glycan structures in the human glycome, as well as limited information about the glycan determinants recognized by glycan-binding proteins (GBPs), which include lectins, receptors, toxins, microbial adhesins, antibodies, and enzymes. Available evidence indicates that GBP binding sites may accommodate glycan determinants made up of 2 to 6 linear monosaccharides, together with their potential side chains containing other sugars and modifications, such as sulfation, phosphorylation, and acetylation. Glycosaminoglycans, including heparin and heparan sulfate, comprise repeating disaccharide motifs, where a linear sequence of 5 to 6 monosaccharides may be required for recognition. Based on our current knowledge of the composition of the glycome and the size of GBP binding sites, glycoproteins and glycolipids may contain approximately 3000 glycan determinants with an additional approximately 4000 theoretical pentasaccharide sequences in glycosaminoglycans. These numbers provide an achievable target for new chemical and/or enzymatic syntheses, and raise new challenges for defining the total glycome and the determinants recognized by GBPs.
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Affiliation(s)
- Richard D Cummings
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Rd. #4001, Atlanta, GA 30322, USA.
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Abstract
More than 25 years after the licensure of aciclovir and then penciclovir, followed by their respective prodrugs valaciclovir and famciclovir, cases of clinically relevant resistance to these drugs in immunocompetent individuals remain very rare. The aim of this review is to focus on the mechanism of action of these anti HSV drugs and then briefly compare this favourable outcome with that of CMV, HIV, HBV and influenza. A central theme is that resistance is an epiphenomenon of failure to suppress virus replication, so that improved potency and selectivity should be prioritised when developing new drugs rather than activity against resistant strains per se.
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Affiliation(s)
- Paul D Griffiths
- Centre for Virology, UCL Medical School, Rowland Hill Street, London NW3 2PF, United Kingdom.
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