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The Contribution of Viral Proteins to the Synergy of Influenza and Bacterial Co-Infection. Viruses 2022; 14:v14051064. [PMID: 35632805 PMCID: PMC9143653 DOI: 10.3390/v14051064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/12/2022] [Accepted: 05/12/2022] [Indexed: 02/04/2023] Open
Abstract
A severe course of acute respiratory disease caused by influenza A virus (IAV) infection is often linked with subsequent bacterial superinfection, which is difficult to cure. Thus, synergistic influenza-bacterial co-infection represents a serious medical problem. The pathogenic changes in the infected host are accelerated as a consequence of IAV infection, reflecting its impact on the host immune response. IAV infection triggers a complex process linked with the blocking of innate and adaptive immune mechanisms required for effective antiviral defense. Such disbalance of the immune system allows for easier initiation of bacterial superinfection. Therefore, many new studies have emerged that aim to explain why viral-bacterial co-infection can lead to severe respiratory disease with possible fatal outcomes. In this review, we discuss the key role of several IAV proteins-namely, PB1-F2, hemagglutinin (HA), neuraminidase (NA), and NS1-known to play a role in modulating the immune defense of the host, which consequently escalates the development of secondary bacterial infection, most often caused by Streptococcus pneumoniae. Understanding the mechanisms leading to pathological disorders caused by bacterial superinfection after the previous viral infection is important for the development of more effective means of prevention; for example, by vaccination or through therapy using antiviral drugs targeted at critical viral proteins.
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Overeem NJ, van der Vries E, Huskens J. A Dynamic, Supramolecular View on the Multivalent Interaction between Influenza Virus and Host Cell. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2007214. [PMID: 33682339 DOI: 10.1002/smll.202007214] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Understanding how influenza viruses traverse the mucus and recognize host cells is critical for evaluating their zoonotic potential, and for prevention and treatment of the disease. The surface of the influenza A virus is covered with the receptor-binding protein hemagglutinin and the receptor-cleaving enzyme neuraminidase, which jointly control the interactions between the virus and the host cell. These proteins are organized in closely spaced trimers and tetramers to facilitate multivalent interactions with sialic acid-terminated glycans. This review shows that the individually weak multivalent interactions of influenza viruses allow superselective binding, virus-induced recruitment of receptors, and the formation of dynamic complexes that facilitate molecular walking. Techniques to measure the avidity and receptor specificity of influenza viruses are reviewed, and the pivotal role of multivalent interactions with their emergent properties in crossing the mucus and entering host cells is discussed. A model is proposed for the initiation of cell entry through virus-induced receptor clustering. The multivalent interactions of influenza viruses are maintained in a dynamic regime by a functional balance between binding and cleaving.
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Affiliation(s)
- Nico J Overeem
- Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, P.O. Box 217, Enschede, 7500 AE, The Netherlands
| | - Erhard van der Vries
- Royal GD, Arnsbergstraat 7, Deventer, 7418 EZ, The Netherlands
- Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht University, Utrecht, 3584CX, The Netherlands
| | - Jurriaan Huskens
- Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, P.O. Box 217, Enschede, 7500 AE, The Netherlands
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Hamming PHE, Overeem NJ, Huskens J. Influenza as a molecular walker. Chem Sci 2020; 11:27-36. [PMID: 32153750 PMCID: PMC7021193 DOI: 10.1039/c9sc05149j] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 11/13/2019] [Indexed: 12/11/2022] Open
Abstract
The surface of the influenza virus is decorated with the receptor-binding protein hemagglutinin (HA) and the receptor-cleaving enzyme neuraminidase (NA). HA is responsible for host cell recognition, while NA prevents aggregation and entrapment, but the intricate mechanism of how the functions of these glycoproteins cooperate and how they are regulated by mutational responses to environmental pressures remains unclear. Recently, several groups have described the motion of influenza over surfaces and reported that this motion is inhibited by NA inhibitors. We argue that the motion of influenza resembles the motility of artificial receptor-cleaving particles called "molecular spiders". The cleaving of receptors by this type of molecular walkers leads to self-avoiding motion across a surface. When the binding and cleaving rates of molecular spiders are balanced, they move both rapidly and efficiently. The studies of molecular spiders offer new insights into the functional balance of HA and NA, but they do not address the asymmetric distribution of HA and NA on the surface of influenza. We propose that receptor-cleaving molecular walkers could play an important role in the further investigation of the motility of influenza viruses.
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Affiliation(s)
- P H Erik Hamming
- Molecular Nanofabrication Group , MESA + Institute for Nanotechnology , Faculty of Science and Technology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands .
| | - Nico J Overeem
- Molecular Nanofabrication Group , MESA + Institute for Nanotechnology , Faculty of Science and Technology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands .
| | - Jurriaan Huskens
- Molecular Nanofabrication Group , MESA + Institute for Nanotechnology , Faculty of Science and Technology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands .
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Du R, Cui Q, Rong L. Competitive Cooperation of Hemagglutinin and Neuraminidase during Influenza A Virus Entry. Viruses 2019; 11:v11050458. [PMID: 31137516 PMCID: PMC6563287 DOI: 10.3390/v11050458] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/17/2019] [Accepted: 05/18/2019] [Indexed: 12/15/2022] Open
Abstract
The hemagglutinin (HA) and neuraminidase (NA) of influenza A virus possess antagonistic activities on interaction with sialic acid (SA), which is the receptor for virus attachment. HA binds SA through its receptor-binding sites, while NA is a receptor-destroying enzyme by removing SAs. The function of HA during virus entry has been extensively investigated, however, examination of NA has long been focused to its role in the exit of progeny virus from infected cells, and the role of NA in the entry process is still under-appreciated. This review summarizes the current understanding of the roles of HA and NA in relation to each other during virus entry.
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Affiliation(s)
- Ruikun Du
- College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, China.
- Shandong Provincial Collaborative Innovation Center for Antiviral Traditional Chinese Medicine, Jinan 250355, China.
- Qingdao Academy of Chinese Medicinal Sciences, Shandong University of Traditional Chinese Medicine, Qingdao 266122, China.
| | - Qinghua Cui
- College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, China.
- Shandong Provincial Collaborative Innovation Center for Antiviral Traditional Chinese Medicine, Jinan 250355, China.
- Qingdao Academy of Chinese Medicinal Sciences, Shandong University of Traditional Chinese Medicine, Qingdao 266122, China.
| | - Lijun Rong
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
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McAuley JL, Gilbertson BP, Trifkovic S, Brown LE, McKimm-Breschkin JL. Influenza Virus Neuraminidase Structure and Functions. Front Microbiol 2019; 10:39. [PMID: 30761095 PMCID: PMC6362415 DOI: 10.3389/fmicb.2019.00039] [Citation(s) in RCA: 236] [Impact Index Per Article: 47.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 01/10/2019] [Indexed: 12/31/2022] Open
Abstract
With the constant threat of emergence of a novel influenza virus pandemic, there must be continued evaluation of the molecular mechanisms that contribute to virulence. Although the influenza A virus surface glycoprotein neuraminidase (NA) has been studied mainly in the context of its role in viral release from cells, accumulating evidence suggests it plays an important, multifunctional role in virus infection and fitness. This review investigates the various structural features of NA, linking these with functional outcomes in viral replication. The contribution of evolving NA activity to viral attachment, entry and release of virions from infected cells, and maintenance of functional balance with the viral hemagglutinin are also discussed. Greater insight into the role of this important antiviral drug target is warranted.
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Affiliation(s)
- Julie L McAuley
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Brad P Gilbertson
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Sanja Trifkovic
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia.,Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN, United States
| | - Lorena E Brown
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Jennifer L McKimm-Breschkin
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
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Yang J, Liu S, Du L, Jiang S. A new role of neuraminidase (NA) in the influenza virus life cycle: implication for developing NA inhibitors with novel mechanism of action. Rev Med Virol 2016; 26:242-50. [PMID: 27061123 PMCID: PMC7169148 DOI: 10.1002/rmv.1879] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Revised: 02/13/2016] [Accepted: 02/17/2016] [Indexed: 11/17/2022]
Abstract
The entire life cycle of influenza virus involves viral attachment, entry, replication, and release. Previous studies have demonstrated that neuraminidase (NA) is an essential glycoprotein on the surface of influenza virus and that it is responsible for release of progeny virions from the host cell to infect new cells. However, recent studies have also suggested that NA may play other roles in the early stages of the viral life cycle, that is, viral attachment and entry. This review focuses on the new role of NA in the early stages of influenza life cycle and the corresponding development of novel NA inhibitors. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Jie Yang
- Key Lab of New Drug Screening of Guangdong Province, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, USA
| | - Shuwen Liu
- Key Lab of New Drug Screening of Guangdong Province, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China
| | - Lanying Du
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, USA
| | - Shibo Jiang
- Key Lab of Medical Molecular Virology of MOE/MOH, Shanghai Medical College, Fudan University, Shanghai, China.,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, USA
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Gao R, Bai T, Li X, Xiong Y, Huang Y, Pan M, Zhang Y, Bo H, Zou S, Shu Y. The comparison of pathology in ferrets infected by H9N2 avian influenza viruses with different genomic features. Virology 2015; 488:149-55. [PMID: 26638019 DOI: 10.1016/j.virol.2015.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 11/11/2015] [Accepted: 11/14/2015] [Indexed: 01/06/2023]
Abstract
H9N2 avian influenza virus circulates widely in poultry and has been responsible for sporadic human infections in several regions. Few studies have been conducted on the pathogenicity of H9N2 AIV isolates that have different genomic features. We compared the pathology induced by a novel reassortant H9N2 virus and two currently circulating H9N2 viruses that have different genomic features in ferrets. The results showed that the three viruses can induce infections with various amounts of viral shedding in ferrets. The novel H9N2 induced respiratory infection, but no pathological lesions were observed in lung tissues. The other two viruses induced mild to intermediate pathological lesions in lung tissues, although the clinical signs presented mildly in ferrets. The pathological lesions presented a diversity consistent with viral replication in ferrets.
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Affiliation(s)
- Rongbao Gao
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China
| | - Tian Bai
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China
| | - Xiaodan Li
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China
| | - Ying Xiong
- Jiangxi Provincial Disease Control and Prevention, Nanchang 330029, China
| | - Yiwei Huang
- Hunan Provincial Disease Control and Prevention, Changsha, China
| | - Ming Pan
- Sichuan Provincial Disease Control and Prevention, Chengdu 610041, China
| | - Ye Zhang
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China
| | - Hong Bo
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China
| | - Shumei Zou
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China
| | - Yuelong Shu
- National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing 102206, China.
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Equine and Canine Influenza H3N8 Viruses Show Minimal Biological Differences Despite Phylogenetic Divergence. J Virol 2015; 89:6860-73. [PMID: 25903329 DOI: 10.1128/jvi.00521-15] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/14/2015] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED The A/H3N8 canine influenza virus (CIV) emerged from A/H3N8 equine influenza virus (EIV) around the year 2000 through the transfer of a single virus from horses to dogs. We defined and compared the biological properties of EIV and CIV by examining their genetic variation, infection, and growth in different cell cultures, receptor specificity, hemagglutinin (HA) cleavage, and infection and growth in horse and dog tracheal explant cultures. Comparison of sequences of viruses from horses and dogs revealed mutations that may be linked to host adaptation and tropism. We prepared infectious clones of representative EIV and CIV strains that were similar to the consensus sequences of viruses from each host. The rescued viruses, including HA and neuraminidase (NA) double reassortants, exhibited similar degrees of long-term growth in MDCK cells. Different host cells showed various levels of susceptibility to infection, but no differences in infectivity were seen when comparing viruses. All viruses preferred α2-3- over α2-6-linked sialic acids for infections, and glycan microarray analysis showed that EIV and CIV HA-Fc fusion proteins bound only to α2-3-linked sialic acids. Cleavage assays showed that EIV and CIV HA proteins required trypsin for efficient cleavage, and no differences in cleavage efficiency were seen. Inoculation of the viruses into tracheal explants revealed similar levels of infection and replication by each virus in dog trachea, although EIV was more infectious in horse trachea than CIV. IMPORTANCE Influenza A viruses can cross species barriers and cause severe disease in their new hosts. Infections with highly pathogenic avian H5N1 virus and, more recently, avian H7N9 virus have resulted in high rates of lethality in humans. Unfortunately, our current understanding of how influenza viruses jump species barriers is limited. Our aim was to provide an overview and biological characterization of H3N8 equine and canine influenza viruses using various experimental approaches, since the canine virus emerged from horses approximately 15 years ago. We showed that although there were numerous genetic differences between the equine and canine viruses, this variation did not result in dramatic biological differences between the viruses from the two hosts, and the viruses appeared phenotypically equivalent in most assays we conducted. These findings suggest that the cross-species transmission and adaptation of influenza viruses may be mediated by subtle changes in virus biology.
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Long-term immunogenicity of an inactivated split-virion 2009 pandemic influenza A H1N1 virus vaccine with or without aluminum adjuvant in mice. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2015; 22:327-35. [PMID: 25589552 DOI: 10.1128/cvi.00662-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In 2009, a global epidemic of influenza A(H1N1) virus caused the death of tens of thousands of people. Vaccination is the most effective means of controlling an epidemic of influenza and reducing the mortality rate. In this study, the long-term immunogenicity of influenza A/California/7/2009 (H1N1) split vaccine was observed as long as 15 months (450 days) after immunization in a mouse model. Female BALB/c mice were immunized intraperitoneally with different doses of aluminum-adjuvanted vaccine. The mice were challenged with a lethal dose (10× 50% lethal dose [LD(50)]) of homologous virus 450 days after immunization. The results showed that the supplemented aluminum adjuvant not only effectively enhanced the protective effect of the vaccine but also reduced the immunizing dose of the vaccine. In addition, the aluminum adjuvant enhanced the IgG antibody level of mice immunized with the H1N1 split vaccine. The IgG level was correlated to the survival rate of the mice. Aluminum-adjuvanted inactivated split-virion 2009 pandemic influenza A H1N1 vaccine has good immunogenicity and provided long-term protection against lethal influenza virus challenge in mice.
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Fusion-related host proteins are actively regulated by NA during influenza infection as revealed by quantitative proteomics analysis. PLoS One 2014; 9:e105947. [PMID: 25153908 PMCID: PMC4143309 DOI: 10.1371/journal.pone.0105947] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Accepted: 07/28/2014] [Indexed: 12/31/2022] Open
Abstract
Three recombinant influenza A viruses with different neuraminidases (NAs) in the background of A/PR/8/34 (PR8), named rPR8-H5N1NA, rPR8-H9N2NA, and rPR8-H1N1NA, derived from H5N1, H9N2, H1N1 (swine) viruses, respectively, were constructed. We performed a quantitative proteomics analysis to investigate differential protein expression in Madin-Darby canine kidney (MDCK) cells infected with recombinant and wild-type influenza viruses to determine whether NA replacement would alter host cell gene expression. Using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-TOF MS) and two-dimensional gel electrophoresis (2-DE), we identified 12 up-regulated and 49 down-regulated protein spots, including cytoskeletal proteins, molecular biosynthesis proteins, ubiquitin-proteasome pathway proteins, and heat shock proteins. The most significant changes in infected cells were observed for molecular biosynthesis proteins. We found more differentially expressed protein spots in cells infected with rPR8-H5N1NA or rPR8-H9N2NA viruses than cells infected with wild-type virus. Many of those proteins are postulated to be involved in cell-cell fusion, but the full mechanism remains to be explored. Meanwhile, our data demonstrate that the wild-type virus has evolutionary advantages over recombinant viruses.
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Krejcova L, Nejdl L, Hynek D, Krizkova S, Kopel P, Adam V, Kizek R. Beads-based electrochemical assay for the detection of influenza hemagglutinin labeled with CdTe quantum dots. Molecules 2013; 18:15573-86. [PMID: 24352014 PMCID: PMC6270527 DOI: 10.3390/molecules181215573] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 11/25/2013] [Accepted: 12/05/2013] [Indexed: 01/11/2023] Open
Abstract
In this study we describe a beads-based assay for rapid, sensitive and specific isolation and detection of influenza vaccine hemagglutinin (HA). Amplification of the hemagglutinin signal resulted from binding of an electrochemical label as quantum dots (QDs). For detection of the metal and protein part of the resulting HA-CdTe complex, two differential pulse voltammetric methods were used. The procedure includes automated robotic isolation and electrochemical analysis of the isolated product. The isolation procedure was based on the binding of paramagnetic particles (MPs) with glycan (Gly), where glycan was used as the specific receptor for linkage of the QD-labeled hemagglutinin.
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Affiliation(s)
| | | | | | | | | | | | - Rene Kizek
- Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
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Chen J, Yan B, Chen Q, Yao Y, Wang H, Liu Q, Zhang S, Wang H, Chen Z. Evaluation of neutralizing efficacy of monoclonal antibodies specific for 2009 pandemic H1N1 influenza A virus in vitro and in vivo. Arch Virol 2013; 159:471-83. [PMID: 24057757 DOI: 10.1007/s00705-013-1852-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 08/07/2013] [Indexed: 12/20/2022]
Abstract
Pandemic influenza A virus (H1N1) 2009 poses a serious public-health challenge worldwide. To characterize the neutralizing epitopes of this virus, we generated a panel of eight monoclonal antibodies (mAbs) against the HA of the A/California/07/2009 virus. The antibodies were specific for the 2009 pdm H1N1 HA, as the antibodies displayed HA-specific ELISA, hemagglutination inhibition (HAI) and neutralization activity. One mAb (mAb12) showed significantly higher HAI and neutralizing titers than the other mAbs. We mapped the antigenic epitopes of the HA by characterizing escape mutants of a 2009 H1N1 vaccine strain (NYMC X-179A). The amino acid changes suggested that these eight mAbs recognized HA antigenic epitopes located in the Sa, Sb, Ca1 and Ca2 sites. Passive immunization with mAbs showed that mAb12 displayed more efficient neutralizing activity in vivo than the other mAbs. mAb12 was also found to be protective, both prophylactically and therapeutically, against a lethal viral challenge in mice. In addition, a single injection of 10 mg/kg mAb12 outperformed a 5-day course of treatment with oseltamivir (10 mg/kg/day by gavage) with respect to both prophylaxis and treatment of lethal viral infection. Taken together, our results showed that mouse-origin mAbs displayed neutralizing effectiveness in vitro and in vivo. One mAb in particular (mAb12) recognized an epitope within the Sb site and demonstrated outstanding neutralizing effectiveness.
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Affiliation(s)
- Jianjun Chen
- Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China,
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