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Rafique S, Rashid F, Mushtaq S, Ali A, Li M, Luo S, Xie L, Xie Z. Global review of the H5N8 avian influenza virus subtype. Front Microbiol 2023; 14:1200681. [PMID: 37333639 PMCID: PMC10272346 DOI: 10.3389/fmicb.2023.1200681] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/15/2023] [Indexed: 06/20/2023] Open
Abstract
Orthomyxoviruses are negative-sense, RNA viruses with segmented genomes that are highly unstable due to reassortment. The highly pathogenic avian influenza (HPAI) subtype H5N8 emerged in wild birds in China. Since its emergence, it has posed a significant threat to poultry and human health. Poultry meat is considered an inexpensive source of protein, but due to outbreaks of HPAI H5N8 from migratory birds in commercial flocks, the poultry meat industry has been facing severe financial crises. This review focuses on occasional epidemics that have damaged food security and poultry production across Europe, Eurasia, the Middle East, Africa, and America. HPAI H5N8 viral sequences have been retrieved from GISAID and analyzed. Virulent HPAI H5N8 belongs to clade 2.3.4.4b, Gs/GD lineage, and has been a threat to the poultry industry and the public in several countries since its first introduction. Continent-wide outbreaks have revealed that this virus is spreading globally. Thus, continuous sero- and viro-surveillance both in commercial and wild birds, and strict biosecurity reduces the risk of the HPAI virus appearing. Furthermore, homologous vaccination practices in commercial poultry need to be introduced to overcome the introduction of emergent strains. This review clearly indicates that HPAI H5N8 is a continuous threat to poultry and people and that further regional epidemiological studies are needed.
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Affiliation(s)
- Saba Rafique
- SB Diagnostic Laboratory, Sadiq Poultry Pvt. Ltd, Rawalpindi, Pakistan
| | - Farooq Rashid
- Department of Infectious Diseases, Chongqing Public Health Medical Center, Chongqing, China
| | - Sajda Mushtaq
- SB Diagnostic Laboratory, Sadiq Poultry Pvt. Ltd, Rawalpindi, Pakistan
| | - Akbar Ali
- Poultry Research Institute, Rawalpindi, Pakistan
| | - Meng Li
- Department of Biotechnology, Guangxi Veterinary Research Institute, Nanning, China
- Guangxi Key Laboratory of Veterinary Biotechnology, Nanning, China
- Key Laboratory of China (Guangxi)-ASEAN Cross-border Animal Disease Prevention and Control, Ministry of Agriculture and Rural Affairs of China, Nanning, China
| | - Sisi Luo
- Department of Biotechnology, Guangxi Veterinary Research Institute, Nanning, China
- Guangxi Key Laboratory of Veterinary Biotechnology, Nanning, China
- Key Laboratory of China (Guangxi)-ASEAN Cross-border Animal Disease Prevention and Control, Ministry of Agriculture and Rural Affairs of China, Nanning, China
| | - Liji Xie
- Department of Biotechnology, Guangxi Veterinary Research Institute, Nanning, China
- Guangxi Key Laboratory of Veterinary Biotechnology, Nanning, China
- Key Laboratory of China (Guangxi)-ASEAN Cross-border Animal Disease Prevention and Control, Ministry of Agriculture and Rural Affairs of China, Nanning, China
| | - Zhixun Xie
- Department of Biotechnology, Guangxi Veterinary Research Institute, Nanning, China
- Guangxi Key Laboratory of Veterinary Biotechnology, Nanning, China
- Key Laboratory of China (Guangxi)-ASEAN Cross-border Animal Disease Prevention and Control, Ministry of Agriculture and Rural Affairs of China, Nanning, China
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Liu H, Wu C, Pang Z, Zhao R, Liao M, Sun H. Phylogenetic and Phylogeographic Analysis of the Highly Pathogenic H5N6 Avian Influenza Virus in China. Viruses 2022; 14:v14081752. [PMID: 36016374 PMCID: PMC9415468 DOI: 10.3390/v14081752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 11/16/2022] Open
Abstract
The clade 2.3.4.4b H5N8 avian influenza viruses (AIVs) have caused the loss of more than 33 million domestic poultry worldwide since January 2020. Novel H5N6 reassortants with hemagglutinin (HA) from clade 2.3.4.4b H5N8 AIVs are responsible for multiple human infections in China. Therefore, we conducted an epidemiological survey on waterfowl farms in Sichuan and Guangxi provinces and performed a comprehensive spatiotemporal analysis of H5N6 AIVs in China. At the nucleotide level, the H5N6 AIVs isolated in the present study exhibited high homology with the H5N6 AIVs that caused human infections. Demographic history indicates that clade 2.3.4.4b seemingly replaced clade 2.3.4.4h to become China’s predominant H5N6 AIV clade. Based on genomic diversity, we classified clade 2.3.4.4b H5N6 AIV into ten genotypes (2.3.4.4bG1–G10), of which the 2.3.4.4bG5 and G10 AIVs can cause human infections. Phylogeographic results suggest that Hong Kong and Jiangxi acted as important epicentres for clades 2.3.4.4b and 2.3.4.4h, respectively. Taken together, our study provides critical insight into the evolution and spread of H5N6 AIVs in China, which indicates that the novel 2.3.4.4b reassortants pose challenges for public health and poultry.
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Affiliation(s)
- Hanlin Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Control and Prevention of Guangdong Province, South China Agricultural University, Guangzhou 510642, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, South China Agricultural University, Guangzhou 510642, China
| | - Changrong Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Control and Prevention of Guangdong Province, South China Agricultural University, Guangzhou 510642, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, South China Agricultural University, Guangzhou 510642, China
| | - Zifeng Pang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Control and Prevention of Guangdong Province, South China Agricultural University, Guangzhou 510642, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, South China Agricultural University, Guangzhou 510642, China
| | - Rui Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Control and Prevention of Guangdong Province, South China Agricultural University, Guangzhou 510642, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, South China Agricultural University, Guangzhou 510642, China
| | - Ming Liao
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
- Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Guangzhou 510640, China
- Correspondence: (M.L.); (H.S.)
| | - Hailiang Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Control and Prevention of Guangdong Province, South China Agricultural University, Guangzhou 510642, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (M.L.); (H.S.)
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Bui CHT, Kuok DIT, Yeung HW, Ng KC, Chu DKW, Webby RJ, Nicholls JM, Peiris JSM, Hui KPY, Chan MCW. Risk Assessment for Highly Pathogenic Avian Influenza A(H5N6/H5N8) Clade 2.3.4.4 Viruses. Emerg Infect Dis 2021; 27:2619-2627. [PMID: 34545790 PMCID: PMC8462306 DOI: 10.3201/eid2710.210297] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The numerous global outbreaks and continuous reassortments of highly pathogenic avian influenza (HPAI) A(H5N6/H5N8) clade 2.3.4.4 viruses in birds pose a major risk to the public health. We investigated the tropism and innate host responses of 5 recent HPAI A(H5N6/H5N8) avian isolates of clades 2.3.4.4b, e, and h in human airway organoids and primary human alveolar epithelial cells. The HPAI A(H5N6/H5N8) avian isolates replicated productively but with lower competence than the influenza A(H1N1)pdm09, HPAI A(H5N1), and HPAI A(H5N6) isolates from humans in both or either models. They showed differential cellular tropism in human airway organoids; some infected all 4 major epithelial cell types: ciliated cells, club cells, goblet cells, and basal cells. Our results suggest zoonotic potential but low transmissibility of the HPAI A(H5N6/H5N8) avian isolates among humans. These viruses induced low levels of proinflammatory cytokines/chemokines, which are unlikely to contribute to the pathogenesis of severe disease.
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Review of Influenza Virus Vaccines: The Qualitative Nature of Immune Responses to Infection and Vaccination Is a Critical Consideration. Vaccines (Basel) 2021; 9:vaccines9090979. [PMID: 34579216 PMCID: PMC8471734 DOI: 10.3390/vaccines9090979] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 08/28/2021] [Accepted: 08/30/2021] [Indexed: 01/06/2023] Open
Abstract
Influenza viruses have affected the world for over a century, causing multiple pandemics. Throughout the years, many prophylactic vaccines have been developed for influenza; however, these viruses are still a global issue and take many lives. In this paper, we review influenza viruses, associated immunological mechanisms, current influenza vaccine platforms, and influenza infection, in the context of immunocompromised populations. This review focuses on the qualitative nature of immune responses against influenza viruses, with an emphasis on trained immunity and an assessment of the characteristics of the host–pathogen that compromise the effectiveness of immunization. We also highlight innovative immunological concepts that are important considerations for the development of the next generation of vaccines against influenza viruses.
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Maegawa K, Sugita S, Arasaki Y, Nerome R, Nerome K. Interleukin 12-containing influenza virus-like-particle vaccine elevate its protective activity against heterotypic influenza virus infection. Heliyon 2020; 6:e04543. [PMID: 32802975 PMCID: PMC7417893 DOI: 10.1016/j.heliyon.2020.e04543] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/03/2020] [Accepted: 07/21/2020] [Indexed: 11/20/2022] Open
Abstract
To produce monovalent and bivalent influenza vaccines composed of virus-like particles (VLPs) containing hemagglutinin (HA), we generated four recombinant Baculoviruses derived from Bombyx mori nuclear polyhedrosis virus (BmNPV) and Autographa california nuclear polyhedrosis virus (AcNPV). Monovalent Fukushima (A/tufted duck/Fukushima/16/2011 [H5N1]) (FkH5) and Anhui (A/Anhui/1/2013 [H7N9]) (AnH7) VLP influenza vaccines were produced in silkworm pupae infected with FkH5-BmNPV or AnH7-BmNPV. To produce a bivalent FkH5 and AnH7 vaccine, the pupae were simultaneously inoculated with FkH5-BmNPV and AnH7-BmNPV. Then, interleukin (IL)-containing bivalent vaccines were produced by Eri silkworm pupae following triple infection with FkH5-AcNPV, AnH7-AcNPV, and IL-12-AcNPV. Fluorescent antibody tests in Sf9 cells triple-infected with FkH5-AcNPV, AnH7-AcNPV, and IL-12-AcNPV showed coexpression of FkH5, AnH7, and IL-12 antigens, suggesting the presence of VLPs containing all three antigens. We then performed competitive hemagglutination inhibition (CHI) tests to calculate the VLP vaccine constituents. Inoculation with two recombinant viruses led to the production of bivalent vaccines containing very similar amounts of the H5 and H7 antigens, suggesting that our dual infection system can be used to produce bivalent VLP vaccines. Immunisation of mice with our developed monovalent and bivalent VLP vaccines induced the production of HI antibody, which protected against a sublethal dose of influenza virus. These IL-12-containing vaccines tended to display increased protection against hetero-subtype influenza viruses.
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Affiliation(s)
- Kenichi Maegawa
- The Institute of Biological Resources, 893-2, Nakayama, Nago-shi, Okinawa 905-0004, Japan
| | - Shigeo Sugita
- Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke-shi, Tochigi 329-0412, Japan
| | - Youta Arasaki
- The Institute of Biological Resources, 893-2, Nakayama, Nago-shi, Okinawa 905-0004, Japan
| | - Reiko Nerome
- The Institute of Biological Resources, 893-2, Nakayama, Nago-shi, Okinawa 905-0004, Japan
| | - Kuniaki Nerome
- The Institute of Biological Resources, 893-2, Nakayama, Nago-shi, Okinawa 905-0004, Japan
- Corresponding author.
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6
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Quantifying within-host diversity of H5N1 influenza viruses in humans and poultry in Cambodia. PLoS Pathog 2020; 16:e1008191. [PMID: 31951644 PMCID: PMC6992230 DOI: 10.1371/journal.ppat.1008191] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 01/30/2020] [Accepted: 11/04/2019] [Indexed: 12/31/2022] Open
Abstract
Avian influenza viruses (AIVs) periodically cross species barriers and infect humans. The likelihood that an AIV will evolve mammalian transmissibility depends on acquiring and selecting mutations during spillover, but data from natural infection is limited. We analyze deep sequencing data from infected humans and domestic ducks in Cambodia to examine how H5N1 viruses evolve during spillover. Overall, viral populations in both species are predominated by low-frequency (<10%) variation shaped by purifying selection and genetic drift, and half of the variants detected within-host are never detected on the H5N1 virus phylogeny. However, we do detect a subset of mutations linked to human receptor binding and replication (PB2 E627K, HA A150V, and HA Q238L) that arose in multiple, independent humans. PB2 E627K and HA A150V were also enriched along phylogenetic branches leading to human infections, suggesting that they are likely human-adaptive. Our data show that H5N1 viruses generate putative human-adapting mutations during natural spillover infection, many of which are detected at >5% frequency within-host. However, short infection times, genetic drift, and purifying selection likely restrict their ability to evolve extensively during a single infection. Applying evolutionary methods to sequence data, we reveal a detailed view of H5N1 virus adaptive potential, and develop a foundation for studying host-adaptation in other zoonotic viruses. H5N1 avian influenza viruses can cross species barriers and cause severe disease in humans. H5N1 viruses currently cannot replicate and transmit efficiently among humans, but animal infection studies and modeling experiments have suggested that human adaptation may require only a few mutations. However, data from natural spillover infection has been limited, posing a challenge for risk assessment. Here, we analyze a unique dataset of deep sequence data from H5N1 virus-infected humans and domestic ducks in Cambodia. We find that well-known markers of human receptor binding and replication arise in multiple, independent humans. We also find that 3 mutations detected within-host are enriched along phylogenetic branches leading to human infections, suggesting that they are likely human-adapting. However, we also show that within-host evolution in both humans and ducks are shaped heavily by purifying selection and genetic drift, and that a large fraction of within-host variation is never detected on the H5N1 phylogeny. Taken together, our data show that H5N1 viruses do generate human-adapting mutations during natural infection. However, short infection times, purifying selection, and genetic drift may severely limit how much H5N1 viruses can evolve during the course of a single infection.
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7
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Hom N, Gentles L, Bloom JD, Lee KK. Deep Mutational Scan of the Highly Conserved Influenza A Virus M1 Matrix Protein Reveals Substantial Intrinsic Mutational Tolerance. J Virol 2019; 93:e00161-19. [PMID: 31019050 PMCID: PMC6580950 DOI: 10.1128/jvi.00161-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 04/09/2019] [Indexed: 12/30/2022] Open
Abstract
Influenza A virus matrix protein M1 is involved in multiple stages of the viral infectious cycle. Despite its functional importance, our present understanding of this essential viral protein is limited. The roles of a small subset of specific amino acids have been reported, but a more comprehensive understanding of the relationship between M1 sequence, structure, and virus fitness remains elusive. In this study, we used deep mutational scanning to measure the effect of every amino acid substitution in M1 on viral replication in cell culture. The map of amino acid mutational tolerance we have generated allows us to identify sites that are functionally constrained in cell culture as well as sites that are less constrained. Several sites that exhibit low tolerance to mutation have been found to be critical for M1 function and production of viable virions. Surprisingly, significant portions of the M1 sequence, especially in the C-terminal domain, whose structure is undetermined, were found to be highly tolerant of amino acid variation, despite having extremely low levels of sequence diversity among natural influenza virus strains. This unexpected discrepancy indicates that not all sites in M1 that exhibit high sequence conservation in nature are under strong constraint during selection for viral replication in cell culture.IMPORTANCE The M1 matrix protein is critical for many stages of the influenza virus infection cycle. Currently, we have an incomplete understanding of this highly conserved protein's function and structure. Key regions of M1, particularly in the C terminus of the protein, remain poorly characterized. In this study, we used deep mutational scanning to determine the extent of M1's tolerance to mutation. Surprisingly, nearly two-thirds of the M1 sequence exhibits a high tolerance for substitutions, contrary to the extremely low sequence diversity observed across naturally occurring M1 isolates. Sites with low mutational tolerance were also identified, suggesting that they likely play critical functional roles and are under selective pressure. These results reveal the intrinsic mutational tolerance throughout M1 and shape future inquiries probing the functions of this essential influenza A virus protein.
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Affiliation(s)
- Nancy Hom
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Lauren Gentles
- Department of Microbiology, University of Washington, Seattle, Washington, USA
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Jesse D Bloom
- Department of Microbiology, University of Washington, Seattle, Washington, USA
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Kelly K Lee
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
- Department of Microbiology, University of Washington, Seattle, Washington, USA
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Nerome K, Matsuda S, Maegawa K, Sugita S, Kuroda K, Kawasaki K, Nerome R. Quantitative analysis of the yield of avian H7 influenza virus haemagglutinin protein produced in silkworm pupae with the use of the codon-optimized DNA: A possible oral vaccine. Vaccine 2017; 35:738-746. [PMID: 28065477 DOI: 10.1016/j.vaccine.2016.12.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 11/25/2016] [Accepted: 12/22/2016] [Indexed: 12/26/2022]
Abstract
In this study, we aimed to quantitatively compare the increased production of three H7 influenza virus-like particle (VLP) haemagglutinin (HA) with the use of a codon-optimized single HA gene in silkworm pupae. Recombinant baculovirus (Korea H7-BmNPV) could produce 0.40 million HA units per pupa, corresponding to 1832μg protein. The yield of the HA produced in larva was estimated to be approximately 0.31 million HA units per larva, and there were no significant differences between the three HA proteins. We could establish efficient recovery system of HA production in larvae and pupae with the use of three cycles sonication methods. Next, we compared yields of HA proteins from three different H7 and two H5 recombinant baculoviruses based on the amount of mRNA synthesized in BmN cells, suggesting that mRNA synthesis may be also a useful indicator for the production of HA. Based on HA titres from four recombinants, the yield of HA had a great influence on the codon-optimized effect and the characteristics of the viral HA gene. The recombinant containing codon optimized HA DNA of A/tufted duck/Fukushima/16/2011 (H5N1) did produce more than one million HA units, although another recombinant including of the wild H5N1 strain failed to show HA activity. Electron microscopy revealed the presence of large VLP and small HA particle in the heavy and light fractions. The purified VLPs reacted with the authentic anti-H7 antibodies and the antibodies prepared after immunization with the VLP H7 antigen. Also H5 and H7VLPs could produce HI antibody in chickens and mice with oral immunization. The antibodies elicited with oral immunization were confirmed in fluorescent antibody analysis and western blotting in Korea H5-BmNPV and H7HA-BmNPV recombinant infected BmN cells. Taken together, these findings provided important insights into future oral vaccine development.
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Affiliation(s)
- Kuniaki Nerome
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan.
| | - Sayaka Matsuda
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan
| | - Kenichi Maegawa
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan
| | - Shigeo Sugita
- Equine Research Institute, Japan Racing Association, 321-4, Tokami-cho, Utsunomiya, Tochigi 320-0856, Japan
| | - Kazumichi Kuroda
- Division of Microbiology, Nihon University School of Medicine, 30-1, Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan
| | - Kazunori Kawasaki
- National Institute of Advanced Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Reiko Nerome
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan
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Nerome K, Sugita S, Kuroda K, Hirose T, Matsuda S, Majima K, Kawasaki K, Shibata T, Poetri ON, Soejoedono RD, Mayasari NLPI, Agungpriyono S, Nerome R. The large-scale production of an artificial influenza virus-like particle vaccine in silkworm pupae. Vaccine 2014; 33:117-25. [PMID: 25448101 DOI: 10.1016/j.vaccine.2014.11.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/09/2014] [Accepted: 11/06/2014] [Indexed: 12/15/2022]
Abstract
We successfully established a mass production system for an influenza virus-like particle (VLP) vaccine using a synthetic H5 hemagglutinin (HA) gene codon-optimized for the silkworm. A recombinant baculovirus containing the synthetic gene was inoculated into silkworm pupae. Four days after inoculation, the hemagglutination titer in homogenates from infected pupae reached a mean value of 0.8 million hemagglutination units (HAU), approximately 2,000 μg HA protein per pupa, more than 50-fold higher than that produced with an embryonated chicken egg. VLPs ranging from 30 nm to 300 nm in diameter and covered with a large number of spikes were detected in the homogenates. The spikes were approximately 14 nm long, similar to an authentic influenza HA spike. Detailed electron micrographs indicated that the VLP spike density was similar to that of authentic influenza virus particles. The results clearly show that the expression of a single HA gene can efficiently produce VLPs in silkworm pupae. When chickens were immunized with the pupae homogenate, the hemagglutination inhibition titer in their sera reached values of 2,048-8,192 after approximately 1 month. This is the first report demonstrating that a large amount of VLP vaccine could be produced by single synthetic HA gene in silkworm pupae. Our system might be useful for future vaccine development against other viral diseases.
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Affiliation(s)
- Kuniaki Nerome
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan.
| | - Shigeo Sugita
- Equine Research Institute, Japan Racing Association, 321-4, Tokami-cho, Utsunomiya, Tochigi 320-0856, Japan
| | - Kazumichi Kuroda
- Division of Microbiology, Nihon University School of Medicine, 30-1, Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan
| | - Toshiharu Hirose
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan
| | - Sayaka Matsuda
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan
| | - Kei Majima
- Baculotechnologies Co., Ltd., 2217-16, Hayashi-cho, Takamatsu, Kagawa 761-0301, Japan
| | - Kazunori Kawasaki
- National Institute of Advanced Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Toshikatsu Shibata
- Division of Gastroenterology and Hepatology, Nihon University School of Medicine, 30-1, Oyaguchi-kamicho, Itabshi-ku, Tokyo 173-8610, Japan
| | - Okti Nadia Poetri
- Faculty of Veterinary Medicine, Bogor Agricultural University IPB, JL Agatis Kampus IPB Darmaga, Bogor 16680, Indonesia
| | - Retno D Soejoedono
- Faculty of Veterinary Medicine, Bogor Agricultural University IPB, JL Agatis Kampus IPB Darmaga, Bogor 16680, Indonesia
| | - Ni L P Ika Mayasari
- Faculty of Veterinary Medicine, Bogor Agricultural University IPB, JL Agatis Kampus IPB Darmaga, Bogor 16680, Indonesia
| | - Srihadi Agungpriyono
- Faculty of Veterinary Medicine, Bogor Agricultural University IPB, JL Agatis Kampus IPB Darmaga, Bogor 16680, Indonesia
| | - Reiko Nerome
- The Institute of Biological Resources, 893-2, Nakayama, Nago, Okinawa 905-0004, Japan
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Salar R, Gahlawat S, Siwach P, Duhan J, Gahlawat SK. Rapid Detection of Viruses Using Loop-Mediated Isothermal Amplification (LAMP): A Review. BIOTECHNOLOGY: PROSPECTS AND APPLICATIONS 2013. [PMCID: PMC7122297 DOI: 10.1007/978-81-322-1683-4_21] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Most of the diseases caused by viral infection are found to be fatal, and the diagnosis is difficult due to confusion with other causative agents. So, a highly efficient molecular-based advance detection technique, i.e., loop-mediated isothermal amplification (LAMP) method, is developed for diagnosis of viral infections by various workers. It is based on amplification of DNA at very low level under isothermal conditions, using a set of four specifically designed primers and a DNA polymerase with strand displacement activity. This technique is found to be superior than most of the molecular techniques like PCR, RT-PCR, and real-time PCR due to its high specificity, sensitivity, and rapidity. Major advantage of LAMP method is its cost-effectiveness as it can be done simply by using water bath or dry bath. Here, in this review information regarding almost all the effective LAMP techniques which is developed so far for diagnosis of numerous viral pathogens is presented.
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Affiliation(s)
- R.K. Salar
- grid.448811.0Department of Biotechnology, Chaudhary Devi Lal University, Sirsa, Haryana India
| | - S.K. Gahlawat
- grid.448811.0Department of Biotechnology, Chaudhary Devi Lal University, Sirsa, Haryana India
| | - P. Siwach
- grid.448811.0Department of Biotechnology, Chaudhary Devi lal University, Sirsa, Haryana India
| | - J.S. Duhan
- grid.448811.0Department of Biotechnology, Chaudhary Devi Lal University, Sirsa, Haryana India
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11
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Comparison of the Infectivity and Transmission of Contemporary Canine and Equine H3N8 Influenza Viruses in Dogs. Vet Med Int 2013; 2013:874521. [PMID: 24198997 PMCID: PMC3808106 DOI: 10.1155/2013/874521] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 08/18/2013] [Accepted: 08/26/2013] [Indexed: 11/17/2022] Open
Abstract
Phylogenetic analyses indicate that canine influenza viruses (CIVs) (H3N8) evolved from contemporary equine influenza virus (EIV). Despite the genetic relatedness of EIV and CIV, recent evidence suggests that CIV is unable to infect, replicate, and spread among susceptible horses. To determine whether equine H3N8 viruses have equally lost the ability to infect, cause disease, and spread among dogs, we evaluated the infectivity and transmissibility of a recent Florida sublineage EIV isolate in dogs. Clinical signs, nasal virus shedding, and serological responses were monitored in dogs for 21 days after inoculation. Real-time reverse transcription-PCR and hemagglutination inhibition assays showed that both the viruses have maintained the ability to infect and replicate in dogs and result in seroconversion. Transmission of EIV from infected to sentinel dogs, however, was restricted. Furthermore, both CIV and EIV exhibited similar sialic acid- α 2,3-gal receptor-binding preferences upon solid-phase binding assays. The results of the in vivo experiments reported here suggesting that dogs are susceptible to EIV and previous reports by members of our laboratory showing limited CIV infection in horses have been mirrored in CIV and EIV infections studies in primary canine and equine respiratory epithelial cells.
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12
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Pabbaraju K, Wong S, Drews SJ. Rethinking approaches to improve the utilization of nucleic acid amplification tests for detection and characterization of influenza A in diagnostic and reference laboratories. Future Microbiol 2011; 6:1443-60. [PMID: 22122441 DOI: 10.2217/fmb.11.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Influenza A virus (IFVA) is a significant cause of respiratory infections worldwide and was also responsible for a recent pandemic in 2009. Laboratory identification of IFVA can guide antiviral therapy, assist in cohorting of patients and prevent antibiotic use. Characterization of the virus can track the emergence of novel strains, identify resistance and determine how circulating strains match with vaccine components. The gold standard for detection and characterization of IFVA is nucleic acid amplification technology (e.g., reverse transcriptase PCR [RT-PCR]), which must contend with a constantly evolving viral genome. Although molecular technology has been available for over two decades, there is still an operational gap between assay design and utilization of these tests for the diagnosis and characterization of IFVA. This review will discuss issues surrounding the implementation and use of RT-PCR for the identification and characterization of IFVA, and speculate on why RT-PCR has not been used more widely in clinical laboratories or moved closer to the patient. Newer, less widely used technologies that may change our laboratory practices will be identified and the authors will close with an attempt to identify some future applications of RT-PCR-based technologies for the detection and characterization of IFVA.
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Affiliation(s)
- Kanti Pabbaraju
- Provincial Laboratory for Public Health, Microbiology, 3030 Hospital Drive NW, Calgary, Alberta T2N 4W4, Canada
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13
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Lee MS, Shih HC, Lu JJ, Su MC, Deng MC, Wu CC, Lin FY, Lin KH, Chen PY, Hsu WL. M-specific reverse transcription loop-mediated isothermal amplification for detection of pandemic (H1N1) 2009 virus. Eur J Clin Invest 2011; 41:434-41. [PMID: 21155764 DOI: 10.1111/j.1365-2362.2010.02427.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Since the initial outbreak in March 2009, the novel pandemic (H1N1) 2009 virus has affected individuals worldwide and caused over 18,138 deaths. There is an urgent need for the development of an easy, accurate and simple method for the diagnosis of this novel pandemic virus. DESIGN Reverse transcription loop-mediated isothermal amplification assay (RT-LAMP) with primers targeting the M segment was established for the rapid differential diagnosis of pandemic (H1N1) 2009 virus. The performance of this assay was characterized using 111 clinic nasopharyngeal swabs, and the diagnosis accuracy was compared with real-time reverse transcription PCR (RRT-PCR) and virus isolation, the latter being the reference standard. RESULTS This method successfully detected pandemic (H1N1) 2009 virus with a detection limit of approximately 20 copies of the target RNA per reaction, which is a comparably sensitivity to the RRT-PCR assay. Furthermore, this assay was able to discriminate pandemic (H1N1) 2009 virus from seasonal influenza viruses, such as H1N1 and H3N2, and other respiratory viruses (parainfluenza type 2 and 3, adenovirus, echovirus 7, and coxsackievirus A10). Based on validation by virus isolation, the specificity and sensitivity of this M-specific RT-LAMP assay were 100% and 98·25%, respectively. Moreover, the RT-LAMP amplification of most positive samples (46 out of 56) was achieved in < 20 min. CONCLUSIONS This is an accurate and fast analysis system suitable for general diagnostic laboratories with only limited equipment, e.g. first-line health care centre. This assay will help clinicians and public health officials to react effectively during an outbreak.
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Affiliation(s)
- Min-Shiuh Lee
- Animal Health Research Institute, Council of Agriculture, Tamsui, Taipei, Taiwan
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14
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Graef KM, Vreede FT, Lau YF, McCall AW, Carr SM, Subbarao K, Fodor E. The PB2 subunit of the influenza virus RNA polymerase affects virulence by interacting with the mitochondrial antiviral signaling protein and inhibiting expression of beta interferon. J Virol 2010; 84:8433-45. [PMID: 20538852 PMCID: PMC2919034 DOI: 10.1128/jvi.00879-10] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 06/05/2010] [Indexed: 11/20/2022] Open
Abstract
The PB2 subunit of the influenza virus RNA polymerase is a major virulence determinant of influenza viruses. However, the molecular mechanisms involved remain unknown. It was previously shown that the PB2 protein, in addition to its nuclear localization, also accumulates in the mitochondria. Here, we demonstrate that the PB2 protein interacts with the mitochondrial antiviral signaling protein, MAVS (also known as IPS-1, VISA, or Cardif), and inhibits MAVS-mediated beta interferon (IFN-beta) expression. In addition, we show that PB2 proteins of influenza viruses differ in their abilities to associate with the mitochondria. In particular, the PB2 proteins of seasonal human influenza viruses localize to the mitochondria while PB2 proteins of avian influenza viruses are nonmitochondrial. This difference in localization is caused by a single amino acid polymorphism in the PB2 mitochondrial targeting signal. In order to address the functional significance of the mitochondrial localization of the PB2 protein in vivo, we have generated two recombinant human influenza viruses encoding either mitochondrial or nonmitochondrial PB2 proteins. We found that the difference in the mitochondrial localization of the PB2 proteins does not affect the growth of these viruses in cell culture. However, the virus encoding the nonmitochondrial PB2 protein induces higher levels of IFN-beta and, in an animal model, is attenuated compared to the isogenic virus encoding a mitochondrial PB2. Overall this study implicates the PB2 protein in the regulation of host antiviral innate immune pathways and suggests an important role for the mitochondrial association of the PB2 protein in determining virulence.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Amino Acid Sequence
- Animals
- Down-Regulation
- Female
- Host-Pathogen Interactions
- Humans
- Influenza A Virus, H1N1 Subtype/enzymology
- Influenza A Virus, H1N1 Subtype/genetics
- Influenza A Virus, H1N1 Subtype/pathogenicity
- Influenza A Virus, H2N2 Subtype/enzymology
- Influenza A Virus, H2N2 Subtype/genetics
- Influenza A Virus, H2N2 Subtype/pathogenicity
- Influenza A Virus, H5N1 Subtype/enzymology
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/pathogenicity
- Influenza A virus/enzymology
- Influenza A virus/genetics
- Influenza A virus/pathogenicity
- Influenza, Human/genetics
- Influenza, Human/metabolism
- Influenza, Human/virology
- Interferon-beta/genetics
- Interferon-beta/metabolism
- Mice
- Mice, Inbred C57BL
- Molecular Sequence Data
- Protein Binding
- RNA-Dependent RNA Polymerase/chemistry
- RNA-Dependent RNA Polymerase/genetics
- RNA-Dependent RNA Polymerase/metabolism
- Sequence Alignment
- Viral Proteins/chemistry
- Viral Proteins/genetics
- Viral Proteins/metabolism
- Virulence
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Affiliation(s)
- Katy M. Graef
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
| | - Frank T. Vreede
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
| | - Yuk-Fai Lau
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
| | - Amber W. McCall
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
| | - Simon M. Carr
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
| | - Kanta Subbarao
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
| | - Ervin Fodor
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Medical Countermeasures (Biological) Laboratory, DMERI, DSO National Laboratories, Singapore 117510
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15
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Korteweg C, Gu J. Pandemic influenza A (H1N1) virus infection and avian influenza A (H5N1) virus infection: a comparative analysis. Biochem Cell Biol 2010; 88:575-87. [PMID: 20651828 DOI: 10.1139/o10-017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The 2009 H1N1 and H5N1 influenza viruses are newly (re-) emerged influenza A viruses (2009 A(H1N1) and A(H5N1), respectively) that have recently posed tremendous health threats in many regions worldwide. With the 2009 outbreak of H1N1 influenza A, the world witnessed the first influenza pandemic of the 21st century. The disease has rapidly spread across the entire globe, and has resulted in hundreds of thousands of cases with confirmed infection. Although characterized by high transmissibility, the virulence and fatality of the 2009 A(H1N1) influenza virus have thus far remained relatively low. The reverse holds true for A(H5N1) influenza; at a fatality rate that exceeds 60%, it is known to cause severe damage to the human respiratory system, but is not presently capable of efficient transmission from human to human. Apart from the clear differences between the two types of influenza, there are some significant similarities that warrant attention. In particular, the more severe and fatal 2009 A(H1N1) influenza cases have shown symptoms similar to those reported in cases of A(H5N1) influenza. Histopathological findings for these cases, to the extent available, also appear to have similarities for both diseases in terms of damage and severity. Here we review important recent publications in this area, and we discuss some of the key commonalities and contrasts between the two influenza A types in terms of their biology, origins, clinical features, pathology and pathogenesis, and receptors and transmissibility.
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Affiliation(s)
- Christine Korteweg
- Department of Pathology, Shantou University Medical College, Shantou, China
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16
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Li YG, Chittaganpitch M, Waicharoen S, Kanai Y, Bai GR, Kameoka M, Takeda N, Ikuta K, Sawanpanyalert P. Characterization of H5N1 influenza viruses isolated from humans in vitro. Virol J 2010; 7:112. [PMID: 20515447 PMCID: PMC2890526 DOI: 10.1186/1743-422x-7-112] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Accepted: 06/01/2010] [Indexed: 12/23/2022] Open
Abstract
Since December 1997, highly pathogenic avian influenza A H5N1viruses have swept through poultry populations across Asian countries and been transmitted into African and European countries. We characterized 6 avian influenza H5N1 viruses isolated from humans in 2004 in Thailand. A highly pathogenic (HP) KAN353 strain showed faster replication and higher virulence in embryonated eggs compared to other strains, especially compared to the low pathogenic (LP) SP83 strain. HP KAN353 also showed strong cytopathogenicity compared to SP83 in Madin-Darby canine kidney cells. Interestingly, LP SP83 induced smaller plaques compared to other strains, especially HP KAN353. PB2 amino acid 627E may contribute to low virulence, whereas either PB2 amino acid 627 K or the combination of 627E/701N seems to be associated with high virulence. The in vitro assays used in this study may provide the basis for assessing the pathogenesis of influenza H5N1 viruses in vivo.
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Affiliation(s)
- Yong-Gang Li
- Thailand-Japan Research Collaboration Center on Emerging and Re-emerging Infections, Muang, Nonthaburi, Thailand.
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17
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Tolnay AE, Baskin CR, Tumpey TM, Sabourin PJ, Sabourin CL, Long JP, Pyles JA, Albrecht RA, García-Sastre A, Katze MG, Bielefeldt-Ohmann H. Extrapulmonary tissue responses in cynomolgus macaques (Macaca fascicularis) infected with highly pathogenic avian influenza A (H5N1) virus. Arch Virol 2010; 155:905-14. [PMID: 20372944 PMCID: PMC2892232 DOI: 10.1007/s00705-010-0662-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 03/16/2010] [Indexed: 01/27/2023]
Abstract
The mechanisms responsible for virulence of influenza viruses in humans remain poorly understood. A prevailing hypothesis is that the highly pathogenic virus isolates cause a severe cytokinemia precipitating acute respiratory distress syndrome and multiple organ dysfunction syndrome. Cynomolgus macaques (Macaca fascicularis) infected with a human highly pathogenic avian influenza (HPAI) H5N1 virus isolate (A/Vietnam/1203/2004) or reassortants of human influenza virus A/Texas/36/91 (H1N1) containing genes from the 1918 pandemic influenza A (H1N1) virus developed severe pneumonia within 24 h postinfection. However, virus spread beyond the lungs was only detected in the H5N1 group, and signs of extrapulmonary tissue reactions, including microglia activation and sustained up-regulation of inflammatory markers, most notably hypoxia inducible factor-1alpha (HIF-1alpha), were largely limited to this group. Extrapulmonary pathology may thus contribute to the morbidities induced by H5N1 viruses.
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Affiliation(s)
- A.-E. Tolnay
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO USA
- Present Address: Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523 USA
| | - C. R. Baskin
- Washington National Primate Research Center, University of Washington, Seattle, WA USA
- Department of Comparative Medicine, University of Washington, Seattle, WA USA
- Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, AZ USA
- Science Foundation Arizona, Phoenix, AZ 85004 USA
| | - T. M. Tumpey
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA USA
| | - P. J. Sabourin
- Battelle Biomedical Research Center, West Jefferson, OH USA
| | - C. L. Sabourin
- Battelle Biomedical Research Center, West Jefferson, OH USA
| | - J. P. Long
- Battelle Biomedical Research Center, West Jefferson, OH USA
| | - J. A. Pyles
- Battelle Biomedical Research Center, West Jefferson, OH USA
- Lovelace Respiratory Research Institute, Albuquerque, NM 87108 USA
| | - R. A. Albrecht
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY USA
| | - A. García-Sastre
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY USA
- Department of Medicine, Division of Infectious Diseases, Mount Sinai School of Medicine, New York, NY USA
- Global Health and Emerging Pathogens Institute, Mount Sinai School of Medicine, New York, NY USA
| | - M. G. Katze
- Washington National Primate Research Center, University of Washington, Seattle, WA USA
- Department of Microbiology, University of Washington, Seattle, WA USA
| | - H. Bielefeldt-Ohmann
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO USA
- School of Veterinary Science, University of Queensland, Gatton Campus, Qld, Australia
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18
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Zhong W, Liu F, Dong L, Lu X, Hancock K, Reinherz EL, Katz JM, Sambhara S. Significant impact of sequence variations in the nucleoprotein on CD8 T cell-mediated cross-protection against influenza A virus infections. PLoS One 2010; 5:e10583. [PMID: 20485501 PMCID: PMC2868023 DOI: 10.1371/journal.pone.0010583] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 04/19/2010] [Indexed: 11/18/2022] Open
Abstract
Background Memory CD8 T cells to influenza A viruses are widely detectable in healthy human subjects and broadly cross-reactive for serologically distinct influenza A virus subtypes. However, it is not clear to what extent such pre-existing cellular immunity can provide cross-subtype protection against novel emerging influenza A viruses. Methodology/Principal Findings We show in the mouse model that naturally occurring sequence variations of the conserved nucleoprotein of the virus significantly impact cross-protection against lethal disease in vivo. When priming and challenge viruses shared identical sequences of the immunodominant, protective NP366/Db epitope, strong cross-subtype protection was observed. However, when they did not share complete sequence identity in this epitope, cross-protection was considerably reduced. Contributions of virus-specific antibodies appeared to be minimal under these circumstances. Detailed analysis revealed that the magnitude of the memory CD8 T cell response triggered by the NP366/Db variants was significantly lower than those triggered by the homologous NP366/Db ligand. It appears that strict specificity of a dominant public TCR to the original NP366/Db ligand may limit the expansion of cross-reactive memory CD8 T cells to the NP366/Db variants. Conclusions/Significance Pre-existing CD8 T cell immunity may provide substantial cross-protection against heterosubtypic influenza A viruses, provided that the priming and the subsequent challenge viruses share the identical sequences of the immunodominant, protective CTL epitopes.
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Affiliation(s)
- Weimin Zhong
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
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19
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Cheung YK, Cheng SCS, Ke Y, Xie Y. Two novel HLA-A*0201 T-cell epitopes in avian H5N1 viral nucleoprotein induced specific immune responses in HHD mice. Vet Res 2009; 41:24. [PMID: 19941812 PMCID: PMC2820229 DOI: 10.1051/vetres/2009071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2009] [Accepted: 11/25/2009] [Indexed: 11/22/2022] Open
Abstract
The influenza A nucleoprotein (NP) is an attractive target for avian flu vaccine development because of its high conversancy in the evolutionary chain of the virus. Here we identified two novel HLA-A*0201 restricted NP epitopes, named H5N1 NP373-381 AMDSNTLEL (NP373) and NP458-466 FQGRGVFEL (NP458), using computational bioinformatic analysis. The NP peptides showed a high binding affinity to HLA-A*0201 on T2 cells, and were able to induce the activation of the cytotoxic T cells in the human peripheral blood mononuclear cells. We examined the potential of using NP373 and NP458 peptide sequences supplemented with a single-chain trimer as potential DNA vaccine candidates in an HHD transgenic mouse model. A gene gun delivery system was used for administrating the vaccine candidates into the animals. The results from cytotoxicity and ELISPOT assays indicated that a significant amount of IFN-γ was secreted by the T cells of the vaccinated mice, and the T cells were able to eliminate the corresponding peptide-loaded T2 cells. The discovery of these novel immunogenic NP peptides provides valuable information for avian flu vaccine design and construction.
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MESH Headings
- Animals
- Biolistics
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- HLA-A Antigens/immunology
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/immunology
- Influenza Vaccines/administration & dosage
- Influenza Vaccines/immunology
- Mice
- Mice, Inbred Strains
- Mice, Knockout
- Mice, Transgenic
- Orthomyxoviridae Infections/immunology
- Orthomyxoviridae Infections/prevention & control
- Specific Pathogen-Free Organisms
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
- Viral Nonstructural Proteins/immunology
- Viral Nonstructural Proteins/metabolism
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20
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Szretter KJ, Gangappa S, Belser JA, Zeng H, Chen H, Matsuoka Y, Sambhara S, Swayne DE, Tumpey TM, Katz JM. Early control of H5N1 influenza virus replication by the type I interferon response in mice. J Virol 2009; 83:5825-34. [PMID: 19297490 PMCID: PMC2681972 DOI: 10.1128/jvi.02144-08] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 02/27/2009] [Indexed: 01/16/2023] Open
Abstract
Widespread distribution of highly pathogenic avian H5N1 influenza viruses in domesticated and wild birds continues to pose a threat to public health, as interspecies transmission of virus has resulted in increasing numbers of human disease cases. Although the pathogenic mechanism(s) of H5N1 influenza viruses has not been fully elucidated, it has been suggested that the ability to evade host innate responses, such as the type I interferon response, may contribute to the virulence of these viruses in mammals. We investigated the role that type I interferons (alpha/beta interferon [IFN-alpha/beta]) might play in H5N1 pathogenicity in vivo, by comparing the kinetics and outcomes of H5N1 virus infection in IFN-alpha/beta receptor (IFN-alpha/betaR)-deficient and SvEv129 wild-type mice using two avian influenza A viruses isolated from humans, A/Hong Kong/483/97 (HK/483) and A/Hong Kong/486/97 (HK/486), which exhibit high and low lethality in mice, respectively. IFN-alpha/betaR-deficient mice experienced significantly more weight loss and more rapid time to death than did wild-type mice. HK/486 virus caused a systemic infection similar to that with HK/483 virus in IFN-alpha/betaR-deficient mice, suggesting a role for IFN-alpha/beta in controlling the systemic spread of this H5N1 virus. HK/483 virus replicated more efficiently than HK/486 virus both in vivo and in vitro. However, replication of both viruses was significantly reduced following pretreatment with IFN-alpha/beta. These results suggest a role for the IFN-alpha/beta response in the control of H5N1 virus replication both in vivo and in vitro, and as such it may provide some degree of protection to the host in the early stages of infection.
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Affiliation(s)
- Kristy J Szretter
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 303331, USA
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21
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Vana G, Westover KM. Origin of the 1918 Spanish influenza virus: a comparative genomic analysis. Mol Phylogenet Evol 2008; 47:1100-10. [PMID: 18353690 DOI: 10.1016/j.ympev.2008.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Revised: 02/05/2008] [Accepted: 02/06/2008] [Indexed: 12/09/2022]
Abstract
To test the avian-origin hypothesis of the 1918 Spanish influenza virus we surveyed influenza sequences from a broad taxonomic distribution and collected 65 full-length genomes representing avian, human and "classic" swine H1N1 lineages in addition to numerous other swine (H1N2, H3N1, and H3N2), human (H2N2, H3N2, and H5N1), and avian (H1N1, H4N6, H5N1, H6N1, H6N6, H6N8, H7N3, H8N4, H9N2, and H13N2) subtypes. Amino acids from all eight segments were concatenated, aligned, and used for phylogenetic analyses. In addition, the genes of the polymerase complex (PB1, PB2, and PA) were analyzed individually. All of our results showed the Brevig-Mission/1918 strain in a position basal to the rest of the clade containing human H1N1s and were consistent with a reassortment hypothesis for the origin of the 1918 virus. Our genome phylogeny further indicates a sister relationship with the "classic" swine H1N1 lineage. The individual PB1, PB2, and PA phylogenies were consistent with reassortment/recombination hypotheses for these genes. These results demonstrate the importance of using a complete-genome approach for addressing the avian-origin hypothesis and predicting the emergence of new pandemic influenza strains.
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Affiliation(s)
- Geoff Vana
- Department of Biology, Winthrop University, Rock Hill, SC 29733, USA
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22
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Hatta M, Hatta Y, Kim JH, Watanabe S, Shinya K, Nguyen T, Lien PS, Le QM, Kawaoka Y. Growth of H5N1 influenza A viruses in the upper respiratory tracts of mice. PLoS Pathog 2007; 3:1374-9. [PMID: 17922570 PMCID: PMC2000968 DOI: 10.1371/journal.ppat.0030133] [Citation(s) in RCA: 247] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Accepted: 07/26/2007] [Indexed: 11/18/2022] Open
Abstract
Highly pathogenic avian H5N1 influenza A viruses have spread throughout Asia, Europe, and Africa, raising serious worldwide concern about their pandemic potential. Although more than 250 people have been infected with these viruses, with a consequent high rate of mortality, the molecular mechanisms responsible for the efficient transmission of H5N1 viruses among humans remain elusive. We used a mouse model to examine the role of the amino acid at position 627 of the PB2 viral protein in efficient replication of H5N1 viruses in the mammalian respiratory tract. Viruses possessing Lys at position 627 of PB2 replicated efficiently in lungs and nasal turbinates, as well as in cells, even at the lower temperature of 33 degrees C. Those viruses possessing Glu at this position replicated less well in nasal turbinates than in lungs, and less well in cells at the lower temperature. These results suggest that Lys at PB2-627 confers to avian H5N1 viruses the advantage of efficient growth in the upper and lower respiratory tracts of mammals. Therefore, efficient viral growth in the upper respiratory tract may provide a platform for the adaptation of avian H5N1 influenza viruses to humans and for efficient person-to-person virus transmission, in the context of changes in other viral properties including specificity for human (sialic acid alpha-2,6-galactose containing) receptors.
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Affiliation(s)
- Masato Hatta
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Yasuko Hatta
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jin Hyun Kim
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Shinji Watanabe
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kyoko Shinya
- The Avian Zoonosis Research Centre, Tottori University, Tottori, Japan
| | - Tung Nguyen
- National Centre for Veterinary Diagnostics, Hanoi, Vietnam
| | | | - Quynh Mai Le
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Yoshihiro Kawaoka
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Institute of Medical Science, University of Tokyo, Tokyo, Japan
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama, Japan
- * To whom correspondence should be addressed. E-mail:
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23
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Mukhtar MM, Rasool ST, Song D, Zhu C, Hao Q, Zhu Y, Wu J. Origin of highly pathogenic H5N1 avian influenza virus in China and genetic characterization of donor and recipient viruses. J Gen Virol 2007; 88:3094-3099. [PMID: 17947535 DOI: 10.1099/vir.0.83129-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genetic analysis of all eight genes of two Nanchang avian influenza viruses, A/Duck/Nanchang/1681/92 (H3N8-1681) and A/Duck/Nanchang/1904/92 (H7N1-1904), isolated from Jiangxi province, China, in 1992, showed that six internal genes of H3N8-1681 virus and five internal (except NS gene) genes of H7N1-1904 virus were closely similar to A/Goose/Guangdong/1/96 (H5N1) virus, the first highly pathogenic avian influenza (HPAI) virus of subtype H5N1 isolated in Asia. The neuraminidase (NA) gene of Gs/Gd/1/96 had the highest genetic similarity with A/Duck/Hokkaido/55/96 (H1N1-55) virus. The haemagglutinin (HA) gene of Gs/Gd/1/96 virus might have originated as a result of mutation of H5 HA gene from A/Swan/Hokkaido/51/96 (H5N3-51)-like viruses. The PA gene of H5N3-51 virus had the highest similarity with Gs/Gd/1/96. This study explains the origin of first Asian HPAI H5N1 virus in Guangdong by the reassortment of Nanchang (close to Guangdong) and Hokkaido (Japan) (H1N1-55 and H5N3-51) viruses. Genetic characteristics of donor and recipient viruses were also studied.
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Affiliation(s)
- Muhammad Mahmood Mukhtar
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China
| | - Sahibzada T Rasool
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China
| | - Degui Song
- College of Life Sciences, Guangxi Normal University, Guilin 541004, P.R. China
| | - Chengliang Zhu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China
| | - Qian Hao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China
| | - Ying Zhu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China
| | - Jianguo Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China
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24
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Landolt GA, Olsen CW. Up to new tricks - a review of cross-species transmission of influenza A viruses. Anim Health Res Rev 2007; 8:1-21. [PMID: 17692139 DOI: 10.1017/s1466252307001272] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Influenza is a highly contagious disease that has burdened both humans and animals since ancient times. In humans, the most dramatic consequences of influenza are associated with periodically occurring pandemics. Pandemics require the emergence of an antigenically novel virus to which the majority of the population lacks protective immunity. Historically, influenza A viruses from animals have contributed to the generation of human pandemic viruses and they may do so again in the future. It is, therefore, critical to understand the epidemiological and molecular mechanisms that allow influenza A viruses to cross species barriers. This review summarizes the current knowledge of influenza ecology, and the viral factors that are thought to determine influenza A virus species specificity.
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Affiliation(s)
- Gabriele A Landolt
- Department of Clinical Sciences, Colorado State University, 300 West Drake Road, Fort Collins, CO 80523, USA.
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25
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Stoloff GA, Caparros-Wanderley W. Synthetic multi-epitope peptides identified in silico induce protective immunity against multiple influenza serotypes. Eur J Immunol 2007; 37:2441-9. [PMID: 17668898 DOI: 10.1002/eji.200737254] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Influenza causes yearly epidemics of mild disease and, occasionally, pandemics with millions of fatalities. Currently, no vaccine is effective against all influenza strains. Analysis of influenza sequences from animal and human isolates using CLUSTALW and a novel proprietary epitope prediction algorithm identified six conserved T cell-reactive regions in several proteins. Immunisation of transgenic mice with a preparation of these six regions as chemically synthesised peptides (FLU-v) induced a specific HLA-A*0201-mediated CD8(+) T cell response. This T cell population also reacted against human cells infected with three non-related influenza strains, confirming that the identified regions contain epitopes naturally presented by infected human cells and conserved amongst non-related viruses. Moreover, FLU-v immunisation significantly increased survival of transgenic mice against lethal challenge with influenza. Overall, FLU-v represents a promising influenza vaccine candidate, obviating the need for yearly vaccinations and allowing the stockpiling and initiation of a worldwide vaccination program in advance of a pandemic outbreak.
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26
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Chen H, Bright RA, Subbarao K, Smith C, Cox NJ, Katz JM, Matsuoka Y. Polygenic virulence factors involved in pathogenesis of 1997 Hong Kong H5N1 influenza viruses in mice. Virus Res 2007; 128:159-63. [PMID: 17521765 DOI: 10.1016/j.virusres.2007.04.017] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Revised: 04/13/2007] [Accepted: 04/15/2007] [Indexed: 10/23/2022]
Abstract
Virulence factors of influenza A (H5N1) viruses collected in 1997 from mammalian hosts were examined using a BALB/c mouse model. Fifteen amino acid (aa) residues in four influenza virus genes which correlated with high- and low-pathogenic phenotypes in mice were identified by analyzing sequence alignments. In addition to these specific residues, the effects of aa residue 627 of the PB2 gene, and the hemagglutinin (HA) and neuraminidase (NA) genes were also investigated using a reverse genetics system established with representative viruses of low (A/Hong Kong/486/97) and high (A/Hong Kong/483/97) pathogenicity for mice. None of 15 aa residues alone had any effect on virulence. The HA and NA genes had a synergistic effect on virulence and the absence of a glycosylation site at aa154 in the HA gene also increased virulence of virus. Multiple genes are involved in virulence of Hong Kong H5N1 influenza A viruses for mice with the presence of lysine at aa627 in the PB2 gene exhibiting a significantly larger effect than the HA and NA genes.
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Affiliation(s)
- Hualan Chen
- Influenza Division, Centers for Disease Control and Prevention, 1600 Clifton Road, N.E., MS-G16, Atlanta, GA 30333, USA
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27
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Macken CA, Webby RJ, Bruno WJ. Genotype turnover by reassortment of replication complex genes from avian influenza A virus. J Gen Virol 2006; 87:2803-2815. [PMID: 16963738 DOI: 10.1099/vir.0.81454-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Reassortment among the RNA segments of Influenza A virus caused the two most recent human influenza pandemics; recently, reassortment has generated viral genotypes associated with outbreaks of avian H5N1 influenza in Asia and Europe. A statistical analysis has been developed for the systematic identification and characterization of reassortant viruses. The analysis was applied to the genes of the replication complex of 152 avian influenza A viruses isolated between 1966 and 2004 from predominantly terrestrial and domestic aquatic avian species. The results indicated that reassortment among these genes was pervasive throughout this period and throughout both the Eurasian and North American lineages of the virus. Evidence is presented that the circulating genotypes of the replication complex are being replaced continually by novel genotypes created by reassortment. No constraints for coordinated reassortment among genes of the replication complex were evident; rather, reassortment almost always proceeded one segment at a time. A maximum-likelihood estimate of the rate of reassortment was derived. For significantly diverged Asian avian influenza A viruses from the period 1991-2004, it was estimated that the median duration between creation of a new genotype and its next segment reassortment was 3 years. Reassortments that introduced previously unobserved influenza genetic material were detected. These findings point to substantial potential for rapid generation of novel avian influenza A viruses, emphasizing the importance of intensive surveillance of these host species in preparation for a possible pandemic.
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Affiliation(s)
- Catherine A Macken
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, T-10 MS-K710, Los Alamos, NM 87545, USA
| | - Richard J Webby
- Department of Infectious Diseases, St Jude Children's Research Hospital, 332 N. Lauderdale, Memphis, TN 38105-2794, USA
| | - William J Bruno
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, T-10 MS-K710, Los Alamos, NM 87545, USA
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28
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Wu G, Yan SM. Mutation trend of hemagglutinin of influenza A virus: a review from a computational mutation viewpoint. Acta Pharmacol Sin 2006; 27:513-26. [PMID: 16626505 PMCID: PMC7091618 DOI: 10.1111/j.1745-7254.2006.00329.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Since 1999 we have developed two computational mutation approaches to analyze the protein primary structure whose methodology and implications were reviewed in 2002. Our first approach is the calculation of predictable and unpredictable portions of amino-acid pairs in a protein, and the second is the calculation of amino-acid distribution rank in a protein. Both approaches provide quantitative measures to present a protein, which we have used to study a number of proteins with numerous mutations such as p53 proteins. More recently, we focussed our efforts on analyzing the proteins mutating frequently over time such as hemagglutinins of influenza A viruses. In this review we summarise our findings and their implications for hemagglutinin mutations in combination with some newly available data. Our approaches throw light on the true nature of genetic heterogeneity of influenza virus hemagglutinins; that is, the protein variability is highly relevant to its amino-acid construction. Using these approaches, we can monitor new mutations from influenza virus hemagglutinins and may predict their mutations in the future.
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Affiliation(s)
- Guang Wu
- Computational Mutation Project, DreamSciTech Consulting, 301, Building 12, Nanyou A-zone, Jiannan Road, Shenzhen 518054, China.
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29
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Ozaki T, Yauchi M, Xin KQ, Hirahara F, Okuda K. Cross-Reactive Protection Against Influenza A Virus by a Topically Applied DNA Vaccine Encoding M Gene With Adjuvant. Viral Immunol 2005; 18:373-80. [PMID: 16035949 DOI: 10.1089/vim.2005.18.373] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The skin is rich with immunocompetent cells and therefore immunization through the skin is an attractive alternative to the invasive vaccination methods currently used. In this study the backs of mice were gently shaved, hydrated, and painted with a DNA vaccine encoding influenza M protein with adjuvant. The immunized mice were then challenged with two mouse-adapted strains of the influenza virus A: A/PR/8/34 (H1N1) and A/Udorn/72 (H3N2). This adjuvanated and topically applied DNA vaccine efficiently induced cytotoxic as well as humoral immune response and provide cross-reactive protection against several strains of influenza A virus. For better protection against virus infection, it will be necessary to select and combine the DNA vaccine with an appropriate adjuvant.
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Affiliation(s)
- Tomomi Ozaki
- Department of Bacteriology Yokohama City University School of Medicine, Yokohama, Japan
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30
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Lu XH, Cho D, Hall H, Rowe T, Mo IP, Sung HW, Kim WJ, Kang C, Cox N, Klimov A, Katz JM. Pathogenesis of and immunity to a new influenza A (H5N1) virus isolated from duck meat. Avian Dis 2003; 47:1135-40. [PMID: 14575129 DOI: 10.1637/0005-2086-47.s3.1135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The outbreak of avian influenza H5N1 in Hong Kong in 1997 raised concerns about the potential for the H5 subtype to cause a human pandemic. In 2001 a new H5N1 virus, A/Duck Meat/Anyang/AVL-1/2001 (A/Dkmt), was isolated from imported duck meat in Korea. The pathogenesis of this virus was investigated in mice. A/Dkmt virus had low infectivity but was lethal for mice at high doses, and at lethal doses, the virus replicated in the brains of infected mice. A/Dkmt virus cross-reacted poorly with ferret antisera raised against human H5N1 viruses, but prior infection with A/Dkmt virus protected mice from death after secondary infection with human H5N1 virus.
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Affiliation(s)
- X H Lu
- Influenza Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, N.E., Atlanta, GA 30333, USA
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31
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Baigent SJ, McCauley JW. Influenza type A in humans, mammals and birds: determinants of virus virulence, host-range and interspecies transmission. Bioessays 2003; 25:657-71. [PMID: 12815721 DOI: 10.1002/bies.10303] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The virulence of a virus is determined by its ability to adversely affect the host cell, host organism or population of host organisms. Influenza A viruses have been responsible for four pandemics of severe human respiratory disease this century. Avian species harbour a large reservoir of influenza virus strains, which can contribute genes to potential new pandemic human strains. The fundamental importance of understanding the role of each of these genes in determining virulence in birds and humans was dramatically emphasised by the recent direct transmission of avian influenza A viruses to humans, causing fatal infection but not community spread. An understanding of the factors involved in transmission between avian and mammalian species should assist in the development of better surveillance strategies for early recognition of influenza A virus strains having human pandemic potential, and possibly in the design of anti-viral strategies.
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Affiliation(s)
- Susan J Baigent
- Division of Molecular Biology, Institute for Animal Health, Newbury, UK.
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32
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Olsen CW, Karasin A, Erickson G. Characterization of a swine-like reassortant H1N2 influenza virus isolated from a wild duck in the United States. Virus Res 2003; 93:115-21. [PMID: 12727349 DOI: 10.1016/s0168-1702(03)00073-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An H1N2 influenza virus (A/Duck/North Carolina/91347/01) (Dk/NC) was isolated from a wild duck in the United States in 2001. Genetic analyses showed that this duck virus has the same human/classical swine/avian reassortant genotype as the H1N2 viruses that have been isolated from pigs and turkeys in the US since 1999. Phylogenetic analyses of each gene segment further confirmed that the Dk/NC virus is closely related to the domestic animal H1N2 isolates. In particular, Dk/NC is most closely related to a swine H1N2 virus also isolated in North Carolina. These two viruses and a phylogenetically-defined subset of additional swine H1N2 viruses share a common mutation in the Sb antigenic site on the hemagglutinin protein. The recovery of Dk/NC from a wild bird raises concerns for further widespread distribution of these H1N2 viruses via waterfowl migration.
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Affiliation(s)
- Christopher W Olsen
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 53717, USA.
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33
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Lu X, Cho D, Hall H, Rowe T, Sung H, Kim W, Kang C, Mo I, Cox N, Klimov A, Katz J. Pathogenicity and antigenicity of a new influenza A (H5N1) virus isolated from duck meat. J Med Virol 2003; 69:553-9. [PMID: 12601764 DOI: 10.1002/jmv.10344] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Avian influenza A viruses are the ancestral origin of all human influenza viruses. The outbreak of highly pathogenic (HP) avian H5N1 in Hong Kong in 1997 highlighted the potential of these viruses to infect and cause severe disease in humans. Since 1999, HP H5N1 viruses were isolated several times from domestic poultry in Asia. In 2001, a HP H5N1 virus, A/Duck/Anyang/AVL-1/2001 (Dk/Anyang), was isolated from imported frozen duck meat in Korea. Because of this novel source of HP H5N1 virus isolation, concerns were raised about the potential for human exposure and infection; we therefore compared the Dk/Anyang virus with HP H5N1 viruses isolated from humans in 1997 in terms of antigenicity and pathogenicity for mammals. At high doses, Dk/Anyang virus caused up to 50% mortality in BALB/c mice, was isolated from the brains and lymphoid organs of mice, and caused lymphopenia. Overall Dk/Anyang virus was substantially less pathogenic for mice than the H5N1 virus isolated from a fatal human case in 1997. Likewise, Dk/Anyang virus was apathogenic for ferrets. Dk/Anyang virus was antigenically distinguishable by hemagglutination-inhibition (HI) assay from human H5N1 viruses isolated in 1997 and avian H5N1 viruses isolated in 2001 in Hong Kong. Nevertheless, prior infection with Dk/Anyang virus protected mice from death after secondary infection with HP human H5N1 viruses. These results indicate that compared with HP human H5N1 viruses, Dk/Anyang virus is substantially less pathogenic for mammalian species. Nevertheless, the novel source of isolation of this avian H5N1 virus must be considered when evaluating the potential risk to public health.
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Affiliation(s)
- X Lu
- Influenza Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
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34
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Snow M, Ritchie R, Arnaud O, Villoing S, Aspehaug V, Cunningham CO. Isolation and characterisation of segment 1 of the infectious salmon anaemia virus genome. Virus Res 2003; 92:99-105. [PMID: 12606081 DOI: 10.1016/s0168-1702(02)00322-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The isolation and characterisation of the largest genomic segment of infectious salmon anaemia virus (ISAV) is reported. Following identification of ISAV-specific clones from a cDNA library, a rapid amplification of cDNA ends-PCR strategy was designed to obtain the sequence of the full length mRNA transcript. The full length open reading frame (ORF) of this gene was shown to be 2169 nucleotides in length, encoding a putative protein of 722 aa. This sequence was demonstrated by RT-PCR to be specific to ISAV-infected cell cultures. The start codon of this ORF was preceded by the ISAV consensus sequence 5' GCTAAGA 3' indicating the full 5' end of the gene to have been obtained. Based on protein size and amino acid composition, this protein was shown to be similar to the PB2 protein of other orthomyxoviruses. Furthermore, a bipartite nuclear localisation signal was identified in the C-terminus of the protein as is found on all of the influenza virus P proteins. Expression of the putative PB2 as a green fluorescent marker protein-fusion protein confirmed that this protein exhibited nuclear localisation in a fish cell line. Sequences of the ISAV segment 1 gene were obtained from Scottish, Norwegian and Canadian ISAV isolates. Analyses confirmed the close genetic relationship between Norwegian and Scottish ISAV and indicated that this segment was among the most conserved of the ISAV genes identified to date. Thus, this evidence strongly suggests that the genomic segment 1 of ISAV encodes a polymerase protein which is thought to be analagous in function to the PB2 protein of influenza viruses.
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Affiliation(s)
- M Snow
- FRS Marine Laboratory, PO Box 101, Victoria Road, Aberdeen AB11 9DB, Scotland, UK
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35
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Abstract
Since 1997, novel viruses of three different subtypes and five different genotypes have emerged as agents of influenza among pigs in North America. The appearance of these viruses is remarkable because there were no substantial changes in the overall epidemiology of swine influenza in the United States and Canada for over 60 years prior to this time. Viruses of the classical H1N1 lineage were virtually the exclusive cause of swine influenza from the time of their initial isolation in 1930 through 1998. Antigenic drift variants of these H1N1 viruses were isolated in 1991-1998, but a much more dramatic antigenic shift occurred with the emergence of H3N2 viruses in 1997-1998. In particular, H3N2 viruses with genes derived from human, swine and avian viruses have become a major cause of swine influenza in North America. In addition, H1N2 viruses that resulted from reassortment between the triple reassortant H3N2 viruses and classical H1N1 swine viruses have been isolated subsequently from pigs in at least six states. Finally, avian H4N6 viruses crossed the species barrier to infect pigs in Canada in 1999. Fortunately, these H4N6 viruses have not been isolated beyond their initial farm of origin. If these viruses spread more widely, they will represent another antigenic shift for our swine population, and could pose a threat to the world's human population. Research on these novel viruses may offer important clues to the genetic basis for interspecies transmission of influenza viruses.
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Affiliation(s)
- Christopher W Olsen
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 53706, USA.
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36
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Chan PKS. Outbreak of avian influenza A(H5N1) virus infection in Hong Kong in 1997. Clin Infect Dis 2002; 34 Suppl 2:S58-64. [PMID: 11938498 DOI: 10.1086/338820] [Citation(s) in RCA: 300] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The first outbreak of avian influenza A(H5N1) virus in humans occurred in Hong Kong in 1997. Infection was confirmed in 18 individuals, 6 of whom died. Infections were acquired by humans directly from chickens, without the involvement of an intermediate host. The outbreak was halted by a territory-wide slaughter of more than 1.5 million chickens at the end of December 1997. The clinical spectrum of H5N1 infection ranges from asymptomatic infection to fatal pneumonitis and multiple organ failure. Reactive hemophagocytic syndrome was the most characteristic pathologic finding and might have contributed to the lymphopenia, liver dysfunction, and abnormal clotting profiles that were observed among patients with severe infection. Rapid diagnosis with the use of reverse-transcription polymerase chain reaction and monoclonal antibody-based immunofluorescent assay were of great clinical value in the management of the outbreak. The experience of the H5N1 outbreak in Hong Kong underscores the importance of continuous surveillance of influenza virus strains in humans and in other animal species.
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Affiliation(s)
- Paul K S Chan
- Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China.
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37
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Shaw M, Cooper L, Xu X, Thompson W, Krauss S, Guan Y, Zhou N, Klimov A, Cox N, Webster R, Lim W, Shortridge K, Subbarao K. Molecular changes associated with the transmission of avian influenza a H5N1 and H9N2 viruses to humans. J Med Virol 2002; 66:107-14. [PMID: 11748666 DOI: 10.1002/jmv.2118] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In order to identify molecular changes associated with the transmission of avian influenza A H5N1 and H9N2 viruses to humans, the internal genes from these viruses were compared to sequences from other avian and human influenza A isolates. Phylogenetically, each of the internal genes of all sixteen of the human H5N1 and both of the H9N2 isolates were closely related to one another and fell into a distinct clade separate from clades formed by the same genes of other avian and human viruses. All six internal genes were most closely related to those of avian isolates circulating in Asia, indicating that reassortment with human strains had not occurred for any of these 18 isolates. Amino acids previously identified as host-specific residues were predominantly avian in the human isolates although most of the proteins also contained residues observed previously only in sequences of human influenza viruses. For the majority of the nonglycoprotein genes, three distinct subgroups could be distinguished on bootstrap analyses of the nucleotide sequences, suggesting multiple introductions of avian virus strains capable of infecting humans. The shared nonglycoprotein gene constellations of the human H5N1 and H9N2 isolates and their detection in avian isolates only since 1997 when the first human infections were detected suggest that this particular gene combination may confer the ability to infect humans and cause disease. J. Med. Virol. 66:107-114, 2002. Published 2002 Wiley-Liss, Inc.
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Affiliation(s)
- M Shaw
- Influenza Branch, Division of Viral and Rickettsial Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
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38
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Saito T, Lim W, Suzuki T, Suzuki Y, Kida H, Nishimura SI, Tashiro M. Characterization of a human H9N2 influenza virus isolated in Hong Kong. Vaccine 2001; 20:125-33. [PMID: 11567756 DOI: 10.1016/s0264-410x(01)00279-1] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Two H9N2 viruses were isolated, for the first time, from humans in Hong Kong in 1999. Isolation of influenza viruses with a novel subtype of the hemagglutinin (HA) drew attention of health care authorities worldwide from the view of pandemic preparedness. Sequence analysis of the HA genes reveals that HA of A/Hong Kong/1073/99 (H9N2) is most closely related to that of A/quail/HK/G1/97 (H9N2) that contains the internal genes similar to those of Hong Kong/97 (H5N1) viruses. Phylogenetic and antigenic analyses demonstrated the diversity among H9 HA. A/Hong Kong/1073/99 was shown to cause a respiratory infection in Syrian hamsters, suggesting that the virus can replicate efficiently in mammalian hosts. We developed a whole virion test vaccine with a formalin-inactivated egg-grown HK1073. Intraperitoneal administration of the vaccine twice to hamsters conferred a complete protection against challenge infection by the MDCK cell-grown homologous virus. Receptor specificity of HK1073 appeared different from that of other avian influenza viruses of H9 subtype which recognize preferentially alpha-2,3 linked sialic acid. Hemagglutination of HK1073 with guinea pig erythrocytes was inhibited by both alpha-2,3 and alpha-2,6 linked sialic acid containing polymers. These data suggested that HK1073 had acquired a broader host range, including humans. Together with data so far available, the present study suggested that isolation of the H9 influenza viruses from humans requires precaution against the emergence of a novel human influenza.
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MESH Headings
- Animals
- Antigens, Viral/immunology
- Asia
- Cattle
- Cells, Cultured
- Chick Embryo
- Child
- Cricetinae
- Dogs
- Europe
- Female
- Glycoconjugates/pharmacology
- Guinea Pigs
- Hemagglutination Tests
- Hemagglutination, Viral
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/physiology
- Hong Kong
- Horses
- Humans
- Influenza A Virus, H9N2 Subtype
- Influenza A virus/classification
- Influenza A virus/genetics
- Influenza A virus/immunology
- Influenza A virus/isolation & purification
- Influenza A virus/physiology
- Influenza Vaccines/immunology
- Influenza, Human/prevention & control
- Influenza, Human/veterinary
- Influenza, Human/virology
- Lung/virology
- Male
- Mesocricetus
- N-Acetylneuraminic Acid/metabolism
- North America
- Phylogeny
- Poultry/virology
- Poultry Diseases/virology
- Receptors, Virus/metabolism
- Sheep
- Species Specificity
- Swine
- Swine Diseases/virology
- Vaccination
- Vaccines, Inactivated
- Virion/immunology
- Virus Cultivation
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Affiliation(s)
- T Saito
- Department of Virology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, Japan.
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39
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Yao Y, Mingay LJ, McCauley JW, Barclay WS. Sequences in influenza A virus PB2 protein that determine productive infection for an avian influenza virus in mouse and human cell lines. J Virol 2001; 75:5410-5. [PMID: 11333926 PMCID: PMC114950 DOI: 10.1128/jvi.75.11.5410-5415.2001] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Reverse genetics was used to analyze the host range of two avian influenza viruses which differ in their ability to replicate in mouse and human cells in culture. Engineered viruses carrying sequences encoding amino acids 362 to 581 of PB2 from a host range variant productively infect mouse and human cells.
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Affiliation(s)
- Y Yao
- School of Animal and Microbial Sciences, University of Reading, Reading, Berkshire RG6 6AJ, United Kingdom
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40
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Mase M, Imada T, Sanada Y, Etoh M, Sanada N, Tsukamoto K, Kawaoka Y, Yamaguchi S. Imported parakeets harbor H9N2 influenza A viruses that are genetically closely related to those transmitted to humans in Hong Kong. J Virol 2001; 75:3490-4. [PMID: 11238878 PMCID: PMC114145 DOI: 10.1128/jvi.75.7.3490-3494.2001] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In 1997 and 1998, H9N2 influenza A viruses were isolated from the respiratory organs of Indian ring-necked parakeets (Psittacula Krameri manillensis) that had been imported from Pakistan to Japan. The two isolates were closely related to each other (>99% as determined by nucleotide analysis of eight RNA segments), indicating that H9N2 viruses of the same lineage were maintained in these birds for at least 1 year. The hemagglutinins and neuraminidases of both isolates showed >97% nucleotide identity with those of H9N2 viruses isolated from humans in Hong Kong in 1999, while the six genes encoding internal proteins were >99% identical to the corresponding genes of H5N1 viruses recovered during the 1997 outbreak in Hong Kong. These results suggest that the H9N2 parakeet viruses originating in Pakistan share an immediate ancestor with the H9N2 human viruses. Thus, influenza A viruses with the potential to be transmitted directly to humans may be circulating in captive birds worldwide.
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Affiliation(s)
- M Mase
- Department of Virology, National Institute of Animal Health, Tsukuba, Ibaraki 305-0856, Japan.
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41
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Katz JM, Lu X, Tumpey TM, Smith CB, Shaw MW, Subbarao K. Molecular correlates of influenza A H5N1 virus pathogenesis in mice. J Virol 2000; 74:10807-10. [PMID: 11044127 PMCID: PMC110957 DOI: 10.1128/jvi.74.22.10807-10810.2000] [Citation(s) in RCA: 164] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Highly pathogenic avian influenza A H5N1 viruses caused an outbreak of human respiratory illness in Hong Kong. Of 15 human H5N1 isolates characterized, nine displayed a high-, five a low-, and one an intermediate-pathogenicity phenotype in the BALB/c mouse model. Sequence analysis determined that five specific amino acids in four proteins correlated with pathogenicity in mice. Alone or in combination, these specific residues are the likely determinants of virulence of human H5N1 influenza viruses in this model.
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Affiliation(s)
- J M Katz
- Influenza Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
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42
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Guan Y, Shortridge KF, Krauss S, Chin PS, Dyrting KC, Ellis TM, Webster RG, Peiris M. H9N2 influenza viruses possessing H5N1-like internal genomes continue to circulate in poultry in southeastern China. J Virol 2000; 74:9372-80. [PMID: 11000205 PMCID: PMC112365 DOI: 10.1128/jvi.74.20.9372-9380.2000] [Citation(s) in RCA: 302] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The transmission of H9N2 influenza viruses to humans and the realization that the A/Hong Kong/156/97-like (H5N1) (abbreviated HK/156/97) genome complex may be present in H9N2 viruses in southeastern China necessitated a study of the distribution and characterization of H9N2 viruses in poultry in the Hong Kong SAR in 1999. Serological studies indicated that H9N2 influenza viruses had infected a high proportion of chickens and other land-based birds (pigeon, pheasant, quail, guinea fowl, and chukka) from southeastern China. Two lineages of H9N2 influenza viruses present in the live-poultry markets were represented by A/Quail/Hong Kong/G1/97 (Qa/HK/G1/97)-like and A/Duck/Hong Kong/Y280/97 (Dk/HK/Y280/97)-like viruses. Up to 16% of cages of quail in the poultry markets contained Qa/HK/G1/97-like viruses, while about 5% of cages of other land-based birds were infected with Dk/HK/Y280/97-like viruses. No reassortant between the two H9N2 virus lineages was detected despite their cocirculation in the poultry markets. Reassortant viruses represented by A/Chicken/Hong Kong/G9/97 (H9N2) were the major H9N2 influenza viruses circulating in the Hong Kong markets in 1997 but have not been detected since the chicken slaughter in 1997. The Qa/HK/G1/97-like viruses were frequently isolated from quail, while Dk/HK/Y280/97-like viruses were predominately associated with chickens. The Qa/HK/G1/97-like viruses were evolving relatively rapidly, especially in their PB2, HA, NP, and NA genes, suggesting that they are in the process of adapting to a new host. Experimental studies showed that both H9N2 lineages were primarily spread by the aerosol route and that neither quail nor chickens showed evidence of disease. The high prevalence of quail infected with Qa/HK/G1/97-like virus that contains six gene segments genetically highly related to HK/156/97 (H5N1) virus emphasizes the need for surveillance of mammals including humans.
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Affiliation(s)
- Y Guan
- Department of Virology and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-2794, USA
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