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Xu N, Wang X, Cai M, Tang X, Yang W, Lu X, Liu X, Hu S, Gu M, Hu J, Gao R, Liu K, Chen Y, Liu X, Wang X. Mutations in HA and PA affect the transmissibility of H7N9 avian influenza virus in chickens. Vet Microbiol 2023; 287:109910. [PMID: 38016409 DOI: 10.1016/j.vetmic.2023.109910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/30/2023] [Accepted: 11/04/2023] [Indexed: 11/30/2023]
Abstract
Low pathogenic (LP) H7N9 avian influenza virus (AIV) emerged in 2013 and had spread widely over several months in China, experienced a noteworthy reduction in isolation rate in poultry and human since 2017. Here, we examined the transmission of H7N9 viruses to better understand viral spread and dissemination mechanisms. Three out of four viruses (2013-2016) could transmit in chickens through direct contact, and airborne transmission was confirmed in the JT157 (2016) virus. However, we did not detect the transmission of the two 2017 viruses, WF69 and AH395, through either direct or airborne exposure. Molecular analysis of genome sequence of two viruses identified eleven mutations located in viral proteins (except for matrix protein), such as PA (K362R and S364N) and HA (D167N, H7 numbering), etc. We explored the genetic determinants that contributed to the difference in transmissibility of the viruses in chickens by generating a series of reassortants in the JT157 background. We found that the replacement of HA gene in JT157 by that of WF69 abrogated the airborne transmission in recipient chickens, whereas the combination of HA and PA replacement led to the loss of airborne and direct contact transmission. Failure with contact transmission of the viruses has been associated with the emergence of the mutations D167N in HA and K362R and S364N in PA. Furthermore, the HA D167N mutation significantly reduced viral attachment to chicken lung and trachea tissues, while mutations K362R and S364N in PA reduced the nuclear transport efficiency and the PA protein expression levels in both cytoplasm and nucleus of CEF cells. The D167N substitution in HA reduced the H7N9 viral acid stability and avian-like receptor binding, while enhanced human-like receptor binding. Further analysis revealed these mutants grew poorly in vitro and in vivo. To conclude, H7N9 AIVs that contain mutations in the HA and PA protein reduced the viral transmissibility in chicken, and may pose a reduced threat for poultry but remain a heightened public health risk.
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Affiliation(s)
- Naiqing Xu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xin Wang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Miao Cai
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xinen Tang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Wenhao Yang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xiaolong Lu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xiaowen Liu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Shunlin Hu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Min Gu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Jiao Hu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Ruyi Gao
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Kaituo Liu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Yu Chen
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Xiaoquan Wang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
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Chiu KHY, Sridhar S, Yuen KY. Preparation for the next pandemic: challenges in strengthening surveillance. Emerg Microbes Infect 2023; 12:2240441. [PMID: 37474466 PMCID: PMC10478602 DOI: 10.1080/22221751.2023.2240441] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 07/22/2023]
Abstract
The devastating Coronavirus Disease 2019 (COVID-19) pandemic indicates that early detection of candidates with pandemic potential is vital. However, comprehensive metagenomic sequencing of the total microbiome is not practical due to the astronomical and rapidly evolving numbers and species of micro-organisms. Analysis of previous pandemics suggests that an increase in human-animal interactions, changes in animal and arthropod distribution due to climate change and deforestation, continuous mutations and interspecies jumping of RNA viruses, and frequent travels are important factors driving pandemic emergence. Besides measures mitigating these factors, surveillance at human-animal interfaces targeting animals with unusual tolerance to viral infections, sick heathcare workers, and workers at high biosafety level laboratories is crucial. Surveillance of sick travellers is important when alerted by an early warning system of a suspected outbreak due to unknown agents. These samples should be screened by multiplex nucleic acid amplification and subsequent unbiased next-generation sequencing. Novel viruses should be isolated in routine cell cultures, complemented by organoid cultures, and then tested in animal models for interspecies transmission potential. Potential agents are candidates for designing rapid diagnostics, therapeutics, and vaccines. For early detection of outbreaks, there are advantages in using event-based surveillance and artificial intelligence (AI), but high background noise and censorship are possible drawbacks. These systems are likely useful if they channel reliable information from frontline healthcare or veterinary workers and large international gatherings. Furthermore, sufficient regulation of high biosafety level laboratories, and stockpiling of broad spectrum antiviral drugs, vaccines, and personal protective equipment are indicated for pandemic preparedness.
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Affiliation(s)
- Kelvin Hei-Yeung Chiu
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, People's Republic of China
| | - Siddharth Sridhar
- State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
- Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - Kwok-Yung Yuen
- State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
- Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
- Department of Infectious Disease and Microbiology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, People’s Republic of China
- Centre for Virology, Vaccinology and Therapeutics, Hong Kong Science and Technology Park, Hong Kong Special Administrative Region, People's Republic of China
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3
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Rigby CV, Sabsay KR, Bisht K, Eggink D, Jalal H, te Velthuis AJW. Evolution of transient RNA structure-RNA polymerase interactions in respiratory RNA virus genomes. Virus Evol 2023; 9:vead056. [PMID: 37692892 PMCID: PMC10492445 DOI: 10.1093/ve/vead056] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/02/2023] [Accepted: 08/24/2023] [Indexed: 09/12/2023] Open
Abstract
RNA viruses are important human pathogens that cause seasonal epidemics and occasional pandemics. Examples are influenza A viruses (IAV) and coronaviruses (CoV). When emerging IAV and CoV spill over to humans, they adapt to evade immune responses and optimize their replication and spread in human cells. In IAV, adaptation occurs in all viral proteins, including the viral ribonucleoprotein (RNP) complex. RNPs consist of a copy of the viral RNA polymerase, a double-helical coil of nucleoprotein, and one of the eight segments of the IAV RNA genome. The RNA segments and their transcripts are partially structured to coordinate the packaging of the viral genome and modulate viral mRNA translation. In addition, RNA structures can affect the efficiency of viral RNA synthesis and the activation of host innate immune response. Here, we investigated if RNA structures that modulate IAV replication processivity, so-called template loops (t-loops), vary during the adaptation of pandemic and emerging IAV to humans. Using cell culture-based replication assays and in silico sequence analyses, we find that the sensitivity of the IAV H3N2 RNA polymerase to t-loops increased between isolates from 1968 and 2017, whereas the total free energy of t-loops in the IAV H3N2 genome was reduced. This reduction is particularly prominent in the PB1 gene. In H1N1 IAV, we find two separate reductions in t-loop free energy, one following the 1918 pandemic and one following the 2009 pandemic. No destabilization of t-loops is observed in the influenza B virus genome, whereas analysis of SARS-CoV-2 isolates reveals destabilization of viral RNA structures. Overall, we propose that a loss of free energy in the RNA genome of emerging respiratory RNA viruses may contribute to the adaption of these viruses to the human population.
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Affiliation(s)
- Charlotte V Rigby
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ 08544, USA
- Department of Pathology, Addenbrooke’s Hospital, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
- Addenbrooke’s Hospital, Public Health England, Hills Road, Cambridge CB2 2QQ, UK
| | - Kimberly R Sabsay
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ 08544, USA
- Carl Icahn Laboratory, Lewis-Sigler Institute, Princeton University, South Drive, Princeton, NJ 08544, USA
| | - Karishma Bisht
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ 08544, USA
| | - Dirk Eggink
- Department of Medical Microbiology, Amsterdam UMC, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Hamid Jalal
- Addenbrooke’s Hospital, Public Health England, Hills Road, Cambridge CB2 2QQ, UK
| | - Aartjan J W te Velthuis
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ 08544, USA
- Center for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Antonie van Leeuwenhoeklaan 9, Bilthoven 3721 MA, the Netherlands
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4
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Rigby C, Sabsay K, Bisht K, Eggink D, Jalal H, te Velthuis AJ. Evolution of transient RNA structure-RNA polymerase interactions in respiratory RNA virus genomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.25.542331. [PMID: 37292879 PMCID: PMC10245964 DOI: 10.1101/2023.05.25.542331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
RNA viruses are important human pathogens that cause seasonal epidemics and occasional pandemics. Examples are influenza A viruses (IAV) and coronaviruses (CoV). When emerging IAV and CoV spill over to humans, they adapt to evade immune responses and optimize their replication and spread in human cells. In IAV, adaptation occurs in all viral proteins, including the viral ribonucleoprotein (RNP) complex. RNPs consists of a copy of the viral RNA polymerase, a double-helical coil of nucleoprotein, and one of the eight segments of the IAV RNA genome. The RNA segments and their transcripts are partially structured to coordinate the packaging of the viral genome and modulate viral mRNA translation. In addition, RNA structures can affect the efficiency of viral RNA synthesis and the activation of host innate immune response. Here, we investigated if RNA structures that modulate IAV replication processivity, so called template loops (t-loops), vary during the adaptation of pandemic and emerging IAV to humans. Using cell culture-based replication assays and in silico sequence analyses, we find that the sensitivity of the IAV H3N2 RNA polymerase to t-loops increased between isolates from 1968 and 2017, whereas the total free energy of t-loops in the IAV H3N2 genome was reduced. This reduction is particularly prominent in the PB1 gene. In H1N1 IAV, we find two separate reductions in t-loop free energy, one following the 1918 pandemic and one following the 2009 pandemic. No destabilization of t-loops is observed in the IBV genome, whereas analysis of SARS-CoV-2 isolates reveals destabilization of viral RNA structures. Overall, we propose that a loss of free energy in the RNA genome of emerging respiratory RNA viruses may contribute to the adaption of these viruses to the human population.
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Affiliation(s)
- Charlotte Rigby
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, 08544 New Jersey, United States
- University of Cambridge, Department of Pathology, Addenbrooke’s Hospital, Cambridge CB2 2QQ, United Kingdom
- Public Health England, Addenbrooke’s Hospital, Cambridge CB2 2QQ, United Kingdom
| | - Kimberly Sabsay
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, 08544 New Jersey, United States
- Sigler Institute, Princeton University, Princeton, NJ 08544, United States
| | - Karishma Bisht
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, 08544 New Jersey, United States
| | - Dirk Eggink
- Department of Medical Microbiology, Amsterdam UMC, Amsterdam, The Netherlands
- Center for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Hamid Jalal
- Public Health England, Addenbrooke’s Hospital, Cambridge CB2 2QQ, United Kingdom
| | - Aartjan J.W. te Velthuis
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, 08544 New Jersey, United States
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5
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Scheibner D, Salaheldin AH, Bagato O, Zaeck LM, Mostafa A, Blohm U, Müller C, Eweas AF, Franzke K, Karger A, Schäfer A, Gischke M, Hoffmann D, Lerolle S, Li X, Abd El-Hamid HS, Veits J, Breithaupt A, Boons GJ, Matrosovich M, Finke S, Pleschka S, Mettenleiter TC, de Vries RP, Abdelwhab EM. Phenotypic effects of mutations observed in the neuraminidase of human origin H5N1 influenza A viruses. PLoS Pathog 2023; 19:e1011135. [PMID: 36745654 PMCID: PMC9934401 DOI: 10.1371/journal.ppat.1011135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 02/16/2023] [Accepted: 01/18/2023] [Indexed: 02/07/2023] Open
Abstract
Global spread and regional endemicity of H5Nx Goose/Guangdong avian influenza viruses (AIV) pose a continuous threat for poultry production and zoonotic, potentially pre-pandemic, transmission to humans. Little is known about the role of mutations in the viral neuraminidase (NA) that accompanied bird-to-human transmission to support AIV infection of mammals. Here, after detailed analysis of the NA sequence of human H5N1 viruses, we studied the role of A46D, L204M, S319F and S430G mutations in virus fitness in vitro and in vivo. Although H5N1 AIV carrying avian- or human-like NAs had similar replication efficiency in avian cells, human-like NA enhanced virus replication in human airway epithelia. The L204M substitution consistently reduced NA activity of H5N1 and nine other influenza viruses carrying NA of groups 1 and 2, indicating a universal effect. Compared to the avian ancestor, human-like H5N1 virus has less NA incorporated in the virion, reduced levels of viral NA RNA replication and NA expression. We also demonstrate increased accumulation of NA at the plasma membrane, reduced virus release and enhanced cell-to-cell spread. Furthermore, NA mutations increased virus binding to human-type receptors. While not affecting high virulence of H5N1 in chickens, the studied NA mutations modulated virulence and replication of H5N1 AIV in mice and to a lesser extent in ferrets. Together, mutations in the NA of human H5N1 viruses play different roles in infection of mammals without affecting virulence or transmission in chickens. These results are important to understand the genetic determinants for replication of AIV in mammals and should assist in the prediction of AIV with zoonotic potential.
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Affiliation(s)
- David Scheibner
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Ahmed H. Salaheldin
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
- Department of Poultry Diseases, Faculty of Veterinary Medicine, Alexandria University, El-Beheira, Egypt
| | - Ola Bagato
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), Water Pollution Research Department, Dokki, Giza, Egypt
| | - Luca M. Zaeck
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Ahmed Mostafa
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), Water Pollution Research Department, Dokki, Giza, Egypt
| | - Ulrike Blohm
- Institute of Immunology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Christin Müller
- Institute of Medical Virology, Justus Liebig University Giessen, Giessen, Germany
| | - Ahmed F. Eweas
- Department of Medicinal Chemistry, National Research Center, Dokki, Giza, Egypt; Department of Science, University of Technology and Applied Sciences-Rustaq, Rustaq, Sultanate of Oman
| | - Kati Franzke
- Institute of Infectology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Axel Karger
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Alexander Schäfer
- Institute of Immunology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Marcel Gischke
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Donata Hoffmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Solène Lerolle
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Xuguang Li
- Centre for Biologics Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON, Canada; Department of Biochemistry, Microbiology and Immunology and Emerging Pathogens Research Centre, University of Ottawa, Ottawa, Ontario, Canada
| | - Hatem S. Abd El-Hamid
- Department of Poultry Diseases, Faculty of Veterinary Medicine, Damanhur University, Al-Buheira, Egypt
| | - Jutta Veits
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Angele Breithaupt
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Geert-Jan Boons
- Department of Chemical Biology & Drug Discovery, Utrecht Institute for Pharmaceutical Science, the Netherlands
| | | | - Stefan Finke
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Stephan Pleschka
- Institute of Medical Virology, Justus Liebig University Giessen, Giessen, Germany
- German Center for Infection Research (DZIF) partner site Giessen-Marburg-Langen, Germany
| | - Thomas C. Mettenleiter
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Robert P. de Vries
- Department of Chemical Biology & Drug Discovery, Utrecht Institute for Pharmaceutical Science, the Netherlands
| | - Elsayed M. Abdelwhab
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
- * E-mail:
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Chauhan RP, Gordon ML. An overview of influenza A virus genes, protein functions, and replication cycle highlighting important updates. Virus Genes 2022; 58:255-269. [PMID: 35471490 DOI: 10.1007/s11262-022-01904-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 04/04/2022] [Indexed: 10/18/2022]
Abstract
The recent research findings on influenza A virus (IAV) genome biology prompted us to present a comprehensive overview of IAV genes, protein functions, and replication cycle. The eight gene segments of the IAV genome encode 17 proteins, each having unique functions contributing to virus fitness in the host. The polymerase genes are essential determinants of IAV pathogenicity and virulence; however, other viral components also play crucial roles in the IAV replication, transmission, and adaptation. Specific adaptive mutations within polymerase (PB2, PB1, and PA) and glycoprotein-hemagglutinin (HA) and neuraminidase (NA) genes, may facilitate interspecies transmission and adaptation of IAV. The HA-NA interplay is essential for establishing the IAV infection; the low pH triggers the inactivation of HA-receptor binding, leading to significantly lower NA activities, indicating that the enzymatic function of NA is dependent on HA binding. While the HA and NA glycoproteins are required to initiate infection, M1, M2, NS1, and NEP proteins are essential for cytoplasmic trafficking of viral ribonucleoproteins (vRNPs) and the assembly of the IAV virions. The mechanisms that enable IAV to exploit the host cell resources to advance the infection are discussed. A comprehensive understanding of IAV genome biology is essential for developing antivirals to combat the IAV disease burden.
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Affiliation(s)
- Ravendra P Chauhan
- School of Laboratory Medicine and Medical Sciences, Nelson R. Mandela School of Medicine, College of Health Sciences, University of KwaZulu-Natal, 719 Umbilo Road, Durban, 4001, South Africa
| | - Michelle L Gordon
- School of Laboratory Medicine and Medical Sciences, Nelson R. Mandela School of Medicine, College of Health Sciences, University of KwaZulu-Natal, 719 Umbilo Road, Durban, 4001, South Africa.
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Liu L, Li Z, Zhou J, Liu J, Li X, Huang W, Xiao N, Wang D. Homologous PB1 gene promotes the replication efficiency of avian influenza H7N4 candidate vaccine virus. Influenza Other Respir Viruses 2022; 16:577-584. [PMID: 35037399 PMCID: PMC8983892 DOI: 10.1111/irv.12954] [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: 09/06/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 11/27/2022] Open
Abstract
Background The first and only case of human infection with the avian influenza A (H7N4) virus in China emerged in 2018. The H7N4 virus was distinct from previous H7N9 viruses and raised public concerns. Therefore, developing a suitable H7N4 candidate vaccine virus (CVV) remains crucial for potential pandemic preparedness. Methods We constructed a reassortant virus with a (6 + 2) genome composition, then introduced the polymerase basic protein 1 (PB1) from a wild‐type virus to develop a (5 + 3) reassortant virus through reverse genetics. We performed whole‐genome sequencing to confirm the genome stability, assessed the growth ability in MDCK cells, and analyzed virus antigenicity using hemagglutination inhibition assays. Subsequently, the effect of homologous PB1 on polymerase activity, viral protein yield, and pathogenicity was assessed. Results The (5 + 3) virus harbouring the homologous PB1 gene exhibited significantly improved growth characteristics, higher viral protein yield, and polymerase activity than the (6 + 2) virus. After successive passage in embryonated eggs, glutamic acid (E) substituted glycine(G) at position 218 (H3 numbering) in the hemagglutinin (HA) gene of both (5 + 3) and (6 + 2) viruses. The substitution improved the growth of the (6 + 2) virus but exhibited no significant effect or alteration on the antigenicity of the (5 + 3) virus. Moreover, the (5 + 3) virus exhibited low pathogenicity in chickens and ferrets. Conclusion Homologous PB1 of the H7N4 virus improves the growth ability while sustaining low pathogenicity. Collectively, the gene composition of the (5 + 3) reassortant virus is a suitable H7N4 CVV for potential pandemic preparedness.
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Affiliation(s)
- Liqi Liu
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Zi Li
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Jianfang Zhou
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Jia Liu
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Xiyan Li
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Weijuan Huang
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Ning Xiao
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
| | - Dayan Wang
- Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, China CDC, Beijing, China
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8
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Zhang Z, Guo F, Roy A, Yang J, Luo W, Shen X, Irwin DM, Chen RA, Shen Y. Evolutionary perspectives and adaptation dynamics of human seasonal influenza viruses from 2009 to 2019: An insight from codon usage. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2021; 96:105067. [PMID: 34487866 DOI: 10.1016/j.meegid.2021.105067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/28/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
The annually recurrent seasonal influenza viruses, namely, influenza A viruses (H1N1/pdm2009 and H3N2) and influenza B viruses, contribute substantially to human disease burden. Elucidation of host adaptation, population dynamics and evolutionary patterns of these viruses contribute to better control of current epidemic situation and bolster efforts towards pandemic preparedness. Present study has been addressed at unraveling the signatures of codon usage and dinucleotide distribution of these seasonal influenza viruses associating with their fitness and ongoing adaptive evolution in human population. Thorough analysis of codon usage adaptation revealed that H3N2 has been exhibited best adapted to human cellular system, which correlate with its highest epidemic intensity as compared with the other seasonal influenza viruses. CpG dinucleotide was found to be strongly avoided among the seasonal influenza viruses with more restraint among influenza B viruses than influenza A viruses, and might be accounted to the strategy of the viral pathogens in evading human immune signals. Dynamic scenes of ongoing evolution in codon usage and elimination of CpG motif among the viruses, which correlate with their distinct host adaption state, signifying the marked impact of selective force operational on the viral genomes, aimed at proficient circulation, enhanced fitness and successful infective manifestations in humans.
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Affiliation(s)
- Zhipeng Zhang
- Zhaoqing Branch Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China; Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Fucheng Guo
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Ayan Roy
- Department of Biotechnology, Lovely Professional University, Punjab, India
| | - Jinjin Yang
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Wen Luo
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xuejuan Shen
- Zhaoqing Branch Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China; Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - David M Irwin
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto M5S 1A8, Canada; Banting and Best Diabetes Centre, University of Toronto, Toronto M5S 1A8, Canada
| | - Rui-Ai Chen
- Zhaoqing Branch Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China; Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Zhaoqing Institute of Biotechnology, Zhaoqing 526238, China.
| | - Yongyi Shen
- Zhaoqing Branch Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China; Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China; Zhaoqing Institute of Biotechnology, Zhaoqing 526238, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China.
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9
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Croze M, Kim Y. Inference of population genetic parameters from an irregular time series of seasonal influenza virus sequences. Genetics 2021; 217:6066165. [PMID: 33724414 DOI: 10.1093/genetics/iyaa039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 12/17/2020] [Indexed: 11/12/2022] Open
Abstract
Basic summary statistics that quantify the population genetic structure of influenza virus are important for understanding and inferring the evolutionary and epidemiological processes. However, the sampling dates of global virus sequences in the last several decades are scattered nonuniformly throughout the calendar. Such temporal structure of samples and the small effective size of viral population hampers the use of conventional methods to calculate summary statistics. Here, we define statistics that overcome this problem by correcting for the sampling-time difference in quantifying a pairwise sequence difference. A simple linear regression method jointly estimates the mutation rate and the level of sequence polymorphism, thus providing an estimate of the effective population size. It also leads to the definition of Wright's FST for arbitrary time-series data. Furthermore, as an alternative to Tajima's D statistic or the site-frequency spectrum, a mismatch distribution corrected for sampling-time differences can be obtained and compared between actual and simulated data. Application of these methods to seasonal influenza A/H3N2 viruses sampled between 1980 and 2017 and sequences simulated under the model of recurrent positive selection with metapopulation dynamics allowed us to estimate the synonymous mutation rate and find parameter values for selection and demographic structure that fit the observation. We found that the mutation rates of HA and PB1 segments before 2007 were particularly high and that including recurrent positive selection in our model was essential for the genealogical structure of the HA segment. Methods developed here can be generally applied to population genetic inferences using serially sampled genetic data.
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Affiliation(s)
- Myriam Croze
- Division of EcoScience, Ewha Womans University, Seoul 03760, Korea
| | - Yuseob Kim
- Division of EcoScience, Ewha Womans University, Seoul 03760, Korea.,Department of Life Science, Ewha Womans University, Seoul 03760, Korea
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10
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Mettier J, Marc D, Sedano L, Da Costa B, Chevalier C, Le Goffic R. Study of the host specificity of PB1-F2-associated virulence. Virulence 2021; 12:1647-1660. [PMID: 34125653 PMCID: PMC8205076 DOI: 10.1080/21505594.2021.1933848] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Influenza A viruses cause important diseases in both human and animal. The PB1-F2 protein is a virulence factor expressed by some influenza viruses. Its deleterious action for the infected host is mostly described in mammals, while the available information is scarce in avian hosts. In this work, we compared the effects of PB1-F2 in avian and mammalian hosts by taking advantage of the zoonotic capabilities of an avian H7N1 virus. In vitro, the H7N1 virus did not behave differently when PB1-F2 was deficient while a H3N2 virus devoid of PB1-F2 was clearly less inflammatory. Likewise, when performing in vivo challenges of either chickens or embryonated eggs, with the wild-type or the PB1-F2 deficient virus, no difference could be observed in terms of mortality, host response or tropism. PB1-F2 therefore does not appear to play a major role as a virulence factor in the avian host. However, when infecting NF-κB-luciferase reporter mice with the H7N1 viruses, a massive PB1-F2-dependent inflammation was quantified, highlighting the host specificity of PB1-F2 virulence. Surprisingly, a chimeric 7:1 H3N2 virus harboring an H7N1-origin segment 2 (i.e. expressing the avian PB1-F2) induced a milder inflammatory response than its PB1-F2-deficient counterpart. This result shows that the pro-inflammatory activity of PB1-F2 is governed by complex mechanisms involving components from both the virus and its infected host. Thus, a mere exchange of segment 2 between strains is not sufficient to transmit the deleterious character of PB1-F2.
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Affiliation(s)
- Joëlle Mettier
- Université Paris-Saclay, INRAE, UVSQ, UMR892 VIM, Jouy-en-Josas, France
| | - Daniel Marc
- UMR1282 Infectiologie Et Santé Publique, INRAE, Nouzilly, France
| | - Laura Sedano
- Université Paris-Saclay, INRAE, UVSQ, UMR892 VIM, Jouy-en-Josas, France
| | - Bruno Da Costa
- Université Paris-Saclay, INRAE, UVSQ, UMR892 VIM, Jouy-en-Josas, France
| | | | - Ronan Le Goffic
- Université Paris-Saclay, INRAE, UVSQ, UMR892 VIM, Jouy-en-Josas, France
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11
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Eiden S, Dijkman R, Zell R, Fuchs J, Kochs G. Using a mouse-adapted A/HK/01/68 influenza virus to analyse the impact of NS1 evolution in codons 196 and 231 on viral replication and virulence. J Gen Virol 2020; 101:587-598. [PMID: 32416749 DOI: 10.1099/jgv.0.001422] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Seasonal influenza viruses circulating between 1918 and 2009 harboured two prevalent genetic variations in the NS1 coding region. A glutamic acid (E)-to-lysine (K) exchange at position 196 was reported to diminish the capacity of NS1 to control interferon induction. Furthermore, alterations at position 231 determine a carboxy-terminal extension of seven amino acids from 230 to 237 residues. Sequence analyses of NS1 of the last 90 years suggest that variations at these two positions are functionally linked. To determine the impact of the two positions on viral replication in vivo, we used a mouse-adapted variant of A/Hong Kong/01/68 (maHK68) (H3N2). maHK68 encodes an NS1 of 237 amino acids with lysine at position 196. A panel of recombinant maHK68 viruses was generated encoding NS1 variants that differed at positions 196 and 231. Our analyses showed a clear effect of the K-196-to-E exchange on interferon induction and virus virulence. These effects were further modulated by the loss of the seven-amino-acid extension. We propose that the combination of NS1 E-196 with the short C-terminal variant conferred a fitness advantage that is reflected by increased virulence in vivo. Notably, this particular NS1 constellation was observed for the pandemic 1918 H1N1 virus.
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Affiliation(s)
- Sebastian Eiden
- Institute of Virology, Medical Center - University of Freiburg, Hermann-Herder-Strasse 11, 79104 Freiburg, Germany
| | - Ronald Dijkman
- Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001 Bern, Switzerland
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
- Institute of Virology and Immunology, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Roland Zell
- Section of Experimental Virology, Institute of Medical Microbiology, Jena University Hospital, Friedrich-Schiller-University, Jena, Hans-Knöll-Strasse 2, 07745 Jena, Germany
| | - Jonas Fuchs
- Institute of Virology, Medical Center - University of Freiburg, Hermann-Herder-Strasse 11, 79104 Freiburg, Germany
| | - Georg Kochs
- Institute of Virology, Medical Center - University of Freiburg, Hermann-Herder-Strasse 11, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79008 Freiburg, Germany
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12
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Guo F, Yang J, Pan J, Liang X, Shen X, Irwin DM, Chen RA, Shen Y. Origin and Evolution of H1N1/pdm2009: A Codon Usage Perspective. Front Microbiol 2020; 11:1615. [PMID: 32760376 PMCID: PMC7372903 DOI: 10.3389/fmicb.2020.01615] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 06/19/2020] [Indexed: 12/21/2022] Open
Abstract
The H1N1/pdm2009 virus is a new triple-reassortant virus. While Eurasian avian-like and triple-reassortant swine influenza viruses are the direct ancestors of H1N1/pdm2009, the classic swine influenza virus facilitate the spectrum of influenza A diversity in pig population when the reassortant events occurred during 1998 to April 2009. The factors that facilitate the final formation of this gene constellation for H1N1/pdm2009 virus from this complex gene pool remain unknown. Since a novel successful virus should efficiently replicate and transmit in their hosts, in this study, we estimated the adaptability of the codon usage patterns of the pool of genes from these lineages of swine influenza viruses to the human expression system. We found that the MP and NA genes of Eurasian avian-like swine influenza viruses, and the PB2, PB1 and PA genes of triple-reassortant swine influenza viruses were best adapted to the human codon usage pattern. As these genes participated in the development of H1N1/pdm2009, they might help in viral replication and strengthen its competitiveness during its emergence. After its emergence in the human population, a gradual optimization of codon usage patterns between 2009 and 2019 to the human codon usage for the H1N1/pdm2009 genes was detected. This reveals that ongoing adaptive evolution, after its original incursion, occurred to further increase the adaptability of overall gene cassette to human expression system.
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Affiliation(s)
- Fucheng Guo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Jinjin Yang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Junbin Pan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xianghui Liang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xuejuan Shen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - David M Irwin
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.,Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Rui-Ai Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Enterprise Key Laboratory of Biotechnology R&D of Veterinary Biological Products, Zhaoqing, China
| | - Yongyi Shen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
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13
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Higher virulence of swine H1N2 influenza viruses containing avian-origin HA and 2009 pandemic PA and NP in pigs and mice. Arch Virol 2020; 165:1141-1150. [PMID: 32222822 PMCID: PMC7223331 DOI: 10.1007/s00705-020-04572-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/31/2020] [Indexed: 01/08/2023]
Abstract
Pigs are capable of harbouring influenza A viruses of human and avian origin in their respiratory tracts and thus act as an important intermediary host to generate novel influenza viruses with pandemic potential by genetic reassortment between the two viruses. Here, we show that two distinct H1N2 swine influenza viruses contain avian-like or classical swine-like hemagglutinins with polymerase acidic (PA) and nucleoprotein (NP) genes from 2009 pandemic H1N1 influenza viruses that were found to be circulating in Korean pigs in 2018. Swine H1N2 influenza virus containing an avian-like hemagglutinin gene had enhanced pathogenicity, causing severe interstitial pneumonia in infected pigs and mice. The mortality rate of mice infected with swine H1N2 influenza virus containing an avian-like hemagglutinin gene was higher by 100% when compared to that of mice infected with swine H1N2 influenza virus harbouring classical swine-like hemagglutinin. Further, chemokines attracting inflammatory cells were strongly induced in lung tissues of pigs and mice infected by swine H1N2 influenza virus containing an avian-like hemagglutinin gene. In conclusion, it is necessary for the well-being of humans and pigs to closely monitor swine influenza viruses containing avian-like hemagglutinin with PA and NP genes from 2009 pandemic H1N1 influenza viruses.
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14
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Wang F, Liu G, Lu Y, Hlasny M, Liu Q, Zhou Y. Acquisition of Avian-Origin PB1 Facilitates Viral RNA Synthesis by the 2009 Pandemic H1N1 Virus Polymerase. Viruses 2020; 12:v12030266. [PMID: 32121117 PMCID: PMC7150768 DOI: 10.3390/v12030266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 11/16/2022] Open
Abstract
The constant crosstalk between the large avian reservoir of influenza A viruses (IAV) and its mammalian hosts drives viral evolution and facilitates their host switching. Direct adaptation of an avian strain to human or reassortment between avian-origin gene segments with that of human strains are the two mechanisms for the emergence of pandemic viruses. While it was suggested that the 1918 pandemic virus is of avian origin, reassortment of 1918 human isolates and avian influenza viruses led to the generation of 1957 and 1968 pandemic viruses. Interestingly, the avian PB1 segment, which encodes the catalytic subunit of IAV polymerase, is present in the 1957 and 1968 pandemic viruses. The biological consequence and molecular basis of such gene exchange remain less well understood. Using the 2009 pandemic H1N1 virus as a model, whose polymerase contains a human-origin PB1 subunit, we demonstrate that the acquisition of an avian PB1 markedly enhances viral RNA synthesis. This enhancement is also effective in the absence of PB2 adaptive mutations, which are key determinants of host switching. Mechanistically, the avian-origin PB1 does not appear to affect polymerase assembly but imparts the reassorted pandemic polymerase-augmented viral primary transcription and replication. Moreover, compared to the parental pandemic polymerase, the reassorted polymerase displays comparable complementary RNA (cRNA)-stabilizing activity but is specifically enhanced in progeny viral RNA (vRNA) synthesis from cRNA in a trans-activating manner. Overall, our results provide the first insight into the mechanism via which avian-origin PB1 enhances viral RNA synthesis of the 2009 pandemic virus polymerase.
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Affiliation(s)
- Fangzheng Wang
- Vaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada; (F.W.); (G.L.); (Y.L.); (M.H.); (Q.L.)
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
| | - Guanqun Liu
- Vaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada; (F.W.); (G.L.); (Y.L.); (M.H.); (Q.L.)
| | - Yao Lu
- Vaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada; (F.W.); (G.L.); (Y.L.); (M.H.); (Q.L.)
| | - Magda Hlasny
- Vaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada; (F.W.); (G.L.); (Y.L.); (M.H.); (Q.L.)
| | - Qiang Liu
- Vaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada; (F.W.); (G.L.); (Y.L.); (M.H.); (Q.L.)
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
| | - Yan Zhou
- Vaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada; (F.W.); (G.L.); (Y.L.); (M.H.); (Q.L.)
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
- Correspondence: ; Tel.: +1-306-966-7716
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15
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Complete genome sequence of a novel reassortant H3N3 avian influenza virus. Arch Virol 2019; 164:2881-2885. [PMID: 31456087 DOI: 10.1007/s00705-019-04386-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 07/30/2019] [Indexed: 10/26/2022]
Abstract
Aquatic birds are known to be a reservoir for the most common influenza A viruses (IAVs). In the annual surveillance program, we collected the feces of migratory birds for the detection of IAVs in South Korea in November 2016. A novel reassorted H3N3 avian influenza virus (AIV) containing genes from viruses of wild and domestic birds was identified and named A/aquatic bird/South Korea/sw006/2016(H3N3). The polymerase basic 2 (PB2) and non-structural (NS) genes of this isolate are most closely related to those of wild-bird-origin AIV, while the polymerase basic 1 (PB1), polymerase acidic (PA), hemagglutinin (HA), nucleoprotein (NP), neuraminidase (NA), and matrix (M) genes are most closely related to those of domestic-bird-origin AIV. A/aquatic bird/South Korea/sw006/2016 contains PA, NP, M, and NS genes were most closely related to those of AIV subtype H4 and PB2, PB1, and HA genes that are most closely related to those of AIV subtype H3N8, while the NA gene was most closely related to those of subtype H10, which was recently detected in humans in China. These results suggest that novel reassortment of AIV strains occurred due to interaction between wild and domestic birds. Hence, we emphasize the need for continued surveillance of avian influenza virus in bird populations.
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16
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Niu T, Zhao X, Jiang J, Yan H, Li Y, Tang S, Li Y, Song D. Evolution and Biological Evaluation of Matrinic Derivatives with Amantadine Fragments As New Anti-Influenza Virus Agents. Molecules 2019; 24:E921. [PMID: 30845734 PMCID: PMC6429159 DOI: 10.3390/molecules24050921] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 11/17/2022] Open
Abstract
A series of novel tricyclic matrinic derivatives with 11-adamantyl substitution were designed, synthesized, and evaluated for their activities against Influenza A H3N2 virus, based on the privileged structure strategy. Structure-activity relationship (SAR) analysis indicated that the introduction of an 11-adamantyl might be helpful for the potency. Among them, compounds 9f and 9j exhibited the promising anti-H3N2 activities with IC50 values of 7.2 μM and 10.2 μM, respectively, better than that of lead 1. Their activities were further confirmed at the protein level. Moreover, compound 9f displayed a high pharmacokinetic (PK) stability profile in whole blood and a safety profile in vivo. In primary mechanism, compound 9f could inhibit the virus replication cycle at early stage by targeting M2 protein, consistent with that of the parent amantadine. This study provided powerful information for further strategic optimization to develop these compounds into a new class of anti-influenza agents.
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Affiliation(s)
- Tianyu Niu
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Xiaoqiang Zhao
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Jing Jiang
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Haiyan Yan
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Yinghong Li
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Sheng Tang
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Yuhuan Li
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
| | - Danqing Song
- Beijing Key Laboratory of Anti-infective Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 10005, China.
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17
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Mostafa A, Abdelwhab EM, Mettenleiter TC, Pleschka S. Zoonotic Potential of Influenza A Viruses: A Comprehensive Overview. Viruses 2018; 10:v10090497. [PMID: 30217093 PMCID: PMC6165440 DOI: 10.3390/v10090497] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/24/2018] [Accepted: 09/13/2018] [Indexed: 02/06/2023] Open
Abstract
Influenza A viruses (IAVs) possess a great zoonotic potential as they are able to infect different avian and mammalian animal hosts, from which they can be transmitted to humans. This is based on the ability of IAV to gradually change their genome by mutation or even reassemble their genome segments during co-infection of the host cell with different IAV strains, resulting in a high genetic diversity. Variants of circulating or newly emerging IAVs continue to trigger global health threats annually for both humans and animals. Here, we provide an introduction on IAVs, highlighting the mechanisms of viral evolution, the host spectrum, and the animal/human interface. Pathogenicity determinants of IAVs in mammals, with special emphasis on newly emerging IAVs with pandemic potential, are discussed. Finally, an overview is provided on various approaches for the prevention of human IAV infections.
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Affiliation(s)
- Ahmed Mostafa
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany.
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), Giza 12622, Egypt.
| | - Elsayed M Abdelwhab
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
| | - Thomas C Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
| | - Stephan Pleschka
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany.
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18
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Ryan KA, Slack GS, Marriott AC, Kane JA, Whittaker CJ, Silman NJ, Carroll MW, Gooch KE. Cellular immune response to human influenza viruses differs between H1N1 and H3N2 subtypes in the ferret lung. PLoS One 2018; 13:e0202675. [PMID: 30192789 PMCID: PMC6128469 DOI: 10.1371/journal.pone.0202675] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 07/13/2018] [Indexed: 11/18/2022] Open
Abstract
Seasonal influenza virus infections cause yearly epidemics which are the source of a significant public health burden worldwide. The ferret model for human influenza A virus (IAV) is widely used and has several advantages over other animal models such as comparable symptomology, similar receptor distribution in the respiratory tract to humans and the ability to be infected with human isolates without the need for adaptation. However, a major disadvantage of the model has been a paucity of reagents for the evaluation of the cellular immune response. Investigation of T-cell mediated immunity in ferrets is crucial to vaccine development and efficacy studies. In this study we have used commercially produced antibodies to ferret interferon gamma (IFN-γ) allowing us to reliably measure influenza-specific IFN-γ as a marker of the cellular immune response using both enzyme-linked immunospot (ELISpot) and enzyme-linked immunosorbent (ELISA) techniques. Here we demonstrate the application of these tools to evaluate cellular immunity in ferrets infected with clinically relevant seasonal H1N1 and H3N2 IAV subtypes at equivalent doses. Using small heparinised blood samples we were able to observe the longitudinal influenza-specific IFN-γ responses of ferrets infected with both seasonal subtypes of IAV and found a notable increase in influenza-specific IFN-γ responses in circulating peripheral blood within 8 days post-infection. Both seasonal strains caused a well-defined pattern of influenza-specific IFN-γ responses in infected ferrets when compared to naïve animals. Additionally, we found that while the influenza specific IFN-γ responses found in peripheral circulating blood were comparable between subtypes, the influenza specific IFN-γ responses found in lung lymphocytes significantly differed. Our results suggest that there is a distinct difference between the ability of the two seasonal influenza strains to establish an infection in the lung of ferrets associated with distinct signatures of acquired immunity.
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Affiliation(s)
- Kathryn A. Ryan
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Gillian S. Slack
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Anthony C. Marriott
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Jennifer A. Kane
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Catherine J. Whittaker
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Nigel J. Silman
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Miles W. Carroll
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
| | - Karen E. Gooch
- National Infection Service, Public Health England, Porton Down, Wiltshire, United Kingdom
- * E-mail:
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19
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Hydrogen Bond Variations of Influenza A Viruses During Adaptation in Human. Sci Rep 2017; 7:14295. [PMID: 29085020 PMCID: PMC5662722 DOI: 10.1038/s41598-017-14533-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 10/11/2017] [Indexed: 01/12/2023] Open
Abstract
Many host specific mutations have been detected in influenza A viruses (IAVs). However, their effects on hydrogen bond (H-bond) variations have rarely been investigated. In this study, 60 host specific sites were identified in the internal proteins of avian and human IAVs, 27 of which contained mutations with effects on H-bonds. Besides, 30 group specific sites were detected in HA and NA. Twenty-six of 36 mutations existing at these group specific sites caused H-bond loss or formation in at least one subtype. The number of mutations in isolations of 2009 pandemic H1N1, human-infecting H5N1 and H7N9 varied. The combinations of mutations and H-bond changes in these three subtypes of IAVs were also different. In addition, the mutations in isolations of H5N1 distributed more scattered than those in 2009 pandemic H1N1 and H7N9. Eight wave specific mutations in isolations of the fifth H7N9 wave were also identified. Three of them, R140K in HA, Y170H in NA, and R340K in PB2, were capable of resulting in H-bond loss. As mentioned above, these host or group or wave specific H-bond variations provide us with a new field of vision for understanding the changes of structural features in the human adaptation of IAVs.
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Genetic analysis of a novel reassortant H11N9 Isolated from waterfowl in South Korea in 2016. Virus Genes 2017; 53:656-660. [PMID: 28386784 DOI: 10.1007/s11262-017-1453-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 04/03/2017] [Indexed: 12/18/2022]
Abstract
Aquatic birds are known to harbor all the known influenza A viruses. In the winter of January 2016, we surveyed influenza A virus in the feces of migratory birds in South Korea. The novel re-assorted H11N9 avian influenza virus, which contains genes from avian influenza viruses of poultry and wild birds, was isolated. The polymerase basic 2 (PB2), polymerase basic 1 (PB1), hemagglutinin (HA), and nucleoprotein (NP) genes were most closely related to those of domestic duck-origin avian influenza viruses, while the non-structural (NS) gene was closely related to that of domestic goose-origin avian influenza virus. The polymerase acidic (PA), neuraminidase (NA), and matrix (M) genes were most similar to those of wild bird-origin avian influenza viruses. Our results suggested that the interaction between wild birds and domestic poultry could possibly create novel re-assorted avian influenza viruses circulating in wild birds.
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Zhang Y, Yao J, Qi X, Liu X, Lu X, Feng G. Geniposide demonstrates anti-inflammatory and antiviral activity against pandemic A/Jiangsu/1/2009 (H1N1) influenza virus infection in vitro and in vivo. Antivir Ther 2017; 22:599-611. [PMID: 28272019 DOI: 10.3851/imp3152] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2017] [Indexed: 12/09/2022]
Abstract
BACKGROUND Influenza A viruses (IAVs) have been a great threat to human health for centuries, without effective control. Geniposide, a main iridoid glycoside compound extracted from Gardenia jasminoides Ellis fruit, possesses various biological activities including anti-inflammation and anti-virus. METHODS Madin-Darby canine kidney (MDCK) cells were infected with pandemic A/Jiangsu/1/2009 (H1N1) influenza virus in vitro. Cytotoxicity and antiviral activity of geniposide were estimated by MTT assay. The influenza respiratory tract infection murine model was established by intranasal instillation of pandemic A/Jiangsu/1/2009 (H1N1) influenza virus. One day after infection, the mice were administered with geniposide (5, 10 or 20 mg/kg/day) or the neuraminidase inhibitor (NAI) peramivir (30 mg/kg/day). Body weight, survival time, viral titre and lung index of the mice were measured. The sandwich enzyme-linked immunosorbent assay (ELISA) was used to examine levels of inflammatory cytokines. RESULTS The data showed that geniposide had little cytotoxicity on MDCK cells and protected them from pandemic A/Jiangsu/1/2009 (H1N1) influenza virus-induced cell injury. In the infected mice, geniposide treatment significantly restored the body weights, decreased the mortality, alleviated viral titres and virus-induced lung lesions. Geniposide substantially inhibited the virus-induced alveolar wall changes, alveolar haemorrhage and neutrophil-infiltration in lung tissues. Levels of inflammatory mediators, including tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-4, IL-6 and IL-10 were also markedly altered after treatment with geniposide. CONCLUSIONS Our investigation suggested that geniposide effectively inhibited cell damage mediated by pandemic A/Jiangsu/1/2009 (H1N1) influenza virus and mitigated virus-induced acute inflammation.
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Affiliation(s)
- Yunshi Zhang
- Department of Respiratory Medicine, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jing Yao
- Department of Respiratory Medicine, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xian Qi
- Department of Acute Infectious Disease Control and Prevention, Jiangsu Province Center for Disease Control and Prevention, Nanjing, China
| | - Xing Liu
- Department of Respiratory Medicine, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xieqin Lu
- Department of Respiratory Medicine, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ganzhu Feng
- Department of Respiratory Medicine, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Mostafa A, Kanrai P, Ziebuhr J, Pleschka S. The PB1 segment of an influenza A virus H1N1 2009pdm isolate enhances the replication efficiency of specific influenza vaccine strains in cell culture and embryonated eggs. J Gen Virol 2016; 97:620-631. [PMID: 26743314 DOI: 10.1099/jgv.0.000390] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Influenza vaccine strains (IVSs) contain the haemagglutinin (HA) and neuraminidase (NA) genome segments of relevant circulating strains in the genetic background of influenza A/PR/8/1934 virus (PR8). Previous work has shown that the nature of the PB1 segment may be a limiting factor for the efficient production of IVSs. Here, we showed that the PB1 segment (PB1Gi) from the 2009 pandemic influenza A virus (IAV) A/Giessen/06/2009 (Gi wt, H1N1pdm) may help to resolve (some of) these limitations. We produced a set of recombinant PR8-derived viruses that contained (i) the HA and NA segments from representative IAV strains (H3N2, H5N1, H7N9, H9N2); (ii) the PB1 segment from PR8 or Gi wt, respectively; and (iii) the remaining five genome segments from PR8. Viruses containing the PB1Gi segment, together with the heterologous HA/NA segments and five PR8 segments (5+2+1), replicated to higher titres compared with their 6+2 counterparts containing six PR8 segments and the equivalent heterologous HA/NA segments. Compared with PB1PR8-containing IVSs, viruses with the PB1Gi segment replicated to higher or similar titres in both cell culture and embryonated eggs, most profoundly IVSs of the H5N1 and H7N9 subtype, which are known to grow poorly in these systems. IVSs containing either the PB1Gi or the cognate PB1 segment of the respective specific HA/NA donor strain showed enhanced or similar virus replication levels. This study suggests that substitution of PB1PR8 with the PB1Gi segment may greatly improve the large-scale production of PR8-derived IVSs, especially of those known to replicate poorly in vitro.
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MESH Headings
- Animals
- Chick Embryo
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/metabolism
- Humans
- Influenza A Virus, H1N1 Subtype/enzymology
- Influenza A Virus, H1N1 Subtype/genetics
- Influenza A Virus, H1N1 Subtype/immunology
- Influenza A Virus, H1N1 Subtype/physiology
- Influenza A Virus, H3N2 Subtype/genetics
- Influenza A Virus, H3N2 Subtype/physiology
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/physiology
- Influenza A Virus, H7N9 Subtype/genetics
- Influenza A Virus, H7N9 Subtype/physiology
- Influenza A Virus, H9N2 Subtype/genetics
- Influenza A Virus, H9N2 Subtype/physiology
- Influenza Vaccines/administration & dosage
- Influenza Vaccines/genetics
- Influenza Vaccines/immunology
- Influenza, Human/epidemiology
- Influenza, Human/prevention & control
- Influenza, Human/virology
- Ovum/virology
- Viral Proteins/genetics
- Viral Proteins/metabolism
- Virus Replication
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Affiliation(s)
- Ahmed Mostafa
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), Dokki, Giza, Egypt
| | - Pumaree Kanrai
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
| | - John Ziebuhr
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
| | - Stephan Pleschka
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
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Chin AWH, Yen HL, Krauss S, Webby RJ, Poon LLM. Recombinant influenza virus with a pandemic H2N2 polymerase complex has a higher adaptive potential than one with seasonal H2N2 polymerase complex. J Gen Virol 2015; 97:611-619. [PMID: 26703222 DOI: 10.1099/jgv.0.000385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The reassortment of influenza viral gene segments plays a key role in the genesis of pandemic strains. All of the last three pandemic viruses contained reassorted polymerase complexes with subunits derived from animal viruses, suggesting that the acquisition of a reassorted polymerase complex might have a role in generating these pandemic viruses. Here, we studied polymerase activities of the pandemic H2N2, seasonal H2N2 and pandemic H3N2 viruses. We observed that the viral ribonucleoprotein (vRNP) of pandemic H2N2 virus has a highly robust activity. The polymerase activity of seasonal H2N2 viruses, however, was much reduced. We further identified three mutations (PB2-I114V, PB1-S261N and PA-D383N) responsible for the reduced activity. To determine the potential impact of viral polymerase activity on the viral life cycle, recombinant H3N2 viruses carrying pandemic and seasonal H2N2 vRNP were studied in cell cultures supplemented with oseltamivir carboxylate and tested for their abilities to develop adaptive or resistant mutations. It was found that the recombinant virus with pandemic H2N2 vRNP was more capable of restoring the viral fitness than the one with seasonal vRNP. These results suggest that a robust vRNP is advantageous to influenza virus to cope with a new selection pressure.
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Affiliation(s)
- Alex W H Chin
- Centre of Influenza Research & School of Public Health, University of Hong Kong, Hong Kong, PR China
| | - Hui-L Yen
- Centre of Influenza Research & School of Public Health, University of Hong Kong, Hong Kong, PR China
| | - Scott Krauss
- Virology Division, Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Richard J Webby
- Virology Division, Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Leo L M Poon
- Centre of Influenza Research & School of Public Health, University of Hong Kong, Hong Kong, PR China
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Czako R, Subbarao K. Refining the approach to vaccines against influenza A viruses with pandemic potential. Future Virol 2015; 10:1033-1047. [PMID: 26587050 DOI: 10.2217/fvl.15.69] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Vaccination is the most effective strategy for prevention and control of influenza. Timely production and deployment of seasonal influenza vaccines is based on an understanding of the epidemiology of influenza and on global disease and virologic surveillance. Experience with seasonal influenza vaccines guided the initial development of pandemic influenza vaccines. A large investment in pandemic influenza vaccines in the last decade has resulted in much progress and a body of information that can now be applied to refine the established paradigm. Critical and complementary considerations for pandemic influenza vaccines include improved assessment of the pandemic potential of animal influenza viruses, proactive development and deployment of pandemic influenza vaccines, and application of novel platforms and strategies for vaccine production and administration.
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Affiliation(s)
- Rita Czako
- Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, MD, USA
| | - Kanta Subbarao
- Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, MD, USA
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