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Mostafa A, Mahmoud SH, Shehata M, Müller C, Kandeil A, El-Shesheny R, Nooh HZ, Kayali G, Ali MA, Pleschka S. PA from a Recent H9N2 (G1-Like) Avian Influenza a Virus (AIV) Strain Carrying Lysine 367 Confers Altered Replication Efficiency and Pathogenicity to Contemporaneous H5N1 in Mammalian Systems. Viruses 2020; 12:v12091046. [PMID: 32962203 PMCID: PMC7551781 DOI: 10.3390/v12091046] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/15/2020] [Accepted: 09/18/2020] [Indexed: 12/03/2022] Open
Abstract
Egypt is a hotspot for H5- and H9-subtype avian influenza A virus (AIV) infections and co-infections in poultry by both subtypes have been frequently reported. However, natural genetic reassortment of these subtypes has not been reported yet. Here, we evaluated the genetic compatibility and replication efficiency of reassortants between recent isolates of an Egyptian H5N1 and a H9N2 AIV (H5N1EGY and H9N2EGY). All internal viral proteins-encoding segments of the contemporaneous G1-like H9N2EGY, expressed individually and in combination in the genetic background of H5N1EGY, were genetically compatible with the other H5N1EGY segments. At 37 °C the replication efficiencies of H5N1EGY reassortants expressing the H9N2EGY polymerase subunits PB2 and PA (H5N1PB2-H9N2EGY, H5N1PA-H9N2EGY) were higher than the wild-type H5N1EGY in Madin-Darby canine kidney (MDCK-II) cells. This could not be correlated to viral polymerase activity as this was found to be improved for H5N1PB2-H9N2EGY, but reduced for H5N1PA-H9N2EGY. At 33 °C and 39 °C, H5N1PB2-H9N2EGY and H5N1PA-H9N2EGY replicated to higher levels than the wild-type H5N1EGY in human Calu-3 and A549 cell lines. Nevertheless, in BALB/c mice both reassortants caused reduced mortality compared to the wild-type H5N1EGY. Genetic analysis of the polymerase-encoding segments revealed that the PAH9N2EGY and PB2H9N2EGY encode for a distinct uncharacterized mammalian-like variation (367K) and a well-known mammalian signature (591K), respectively. Introducing the single substitution 367K into the PA of H5N1EGY enabled the mutant virus H5N1PA-R367K to replicate more efficiently at 37 °C in primary human bronchial epithelial (NHBE) cells and also in A549 and Calu-3 cells at 33 °C and 39 °C. Furthermore, H5N1PA-R367K caused higher mortality in BALB/c mice. These findings demonstrate that H5N1 (Clade 2.2.1.2) reassortants carrying internal proteins-encoding segments of G1-like H9N2 viruses can emerge and may gain improved replication fitness. Thereby such H5N1/H9N2 reassortants could augment the zoonotic potential of H5N1 viruses, especially by acquiring unique mammalian-like aa signatures.
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Affiliation(s)
- Ahmed Mostafa
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), 12622 Giza, Egypt; (S.H.M.); (M.S.); (A.K.); (R.E.-S.)
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35390 Giessen, Germany;
- Correspondence: (A.M); (M.A.A.); (S.P.)
| | - Sara H. Mahmoud
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), 12622 Giza, Egypt; (S.H.M.); (M.S.); (A.K.); (R.E.-S.)
| | - Mahmoud Shehata
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), 12622 Giza, Egypt; (S.H.M.); (M.S.); (A.K.); (R.E.-S.)
| | - Christin Müller
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35390 Giessen, Germany;
| | - Ahmed Kandeil
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), 12622 Giza, Egypt; (S.H.M.); (M.S.); (A.K.); (R.E.-S.)
| | - Rabeh El-Shesheny
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), 12622 Giza, Egypt; (S.H.M.); (M.S.); (A.K.); (R.E.-S.)
- St. Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Hanaa Z. Nooh
- Anatomy and Embryology Department, Faculty of Medicine, Jouf University, Sakaka 2014, Saudi Arabia;
| | - Ghazi Kayali
- Department of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas, Houston, TX 77030, USA;
- Human Link, Baabda 1109, Lebanon
| | - Mohamed A. Ali
- Center of Scientific Excellence for Influenza Viruses, National Research Centre (NRC), 12622 Giza, Egypt; (S.H.M.); (M.S.); (A.K.); (R.E.-S.)
- Correspondence: (A.M); (M.A.A.); (S.P.)
| | - Stephan Pleschka
- Institute of Medical Virology, Justus Liebig University Giessen, Schubertstrasse 81, 35390 Giessen, Germany;
- Correspondence: (A.M); (M.A.A.); (S.P.)
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Irradiation by a Combination of Different Peak-Wavelength Ultraviolet-Light Emitting Diodes Enhances the Inactivation of Influenza A Viruses. Microorganisms 2020; 8:microorganisms8071014. [PMID: 32650492 PMCID: PMC7409356 DOI: 10.3390/microorganisms8071014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 12/30/2022] Open
Abstract
Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock. This study aimed to determine the ideal irradiation by ultraviolet-light emitting diodes (UV-LEDs) for IAV disinfection. We irradiated the IAV H1N1 subtype with 4.8 mJ/cm2 UV using eight UV-LEDs [peak wavelengths (WL) = 365, 310, 300, 290, 280, 270, and 260 nm)] or a mercury low pressure (LP)-UV lamp (Peak WL = 254 nm). Inactivation was evaluated by the infection ratio of Madin–Darby canine kidney (MDCK) cells or chicken embryonated eggs. Irradiation by the 260 nm UV-LED showed the highest inactivation among all treatments. Because the irradiation-induced inactivation effects strongly correlated with damage to viral RNA, we calculated the correlation coefficient (RAE) between the irradiant spectrum and absorption of viral RNA. The RAE scores strongly correlated with the inactivation by the UV-LEDs and LP-UV lamp. To increase the RAE score, we combined three different peak WL UV-LEDs (hybrid UV-LED). The hybrid UV-LED (RAE = 86.3) significantly inactivated both H1N1 and H6N2 subtypes to a greater extent than 260 nm (RAE = 68.6) or 270 nm (RAE = 42.2) UV-LEDs. The RAE score is an important factor for increasing the virucidal effects of UV-LED irradiation.
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Morse SS, Qureshi H. Acute respiratory infections in the WHO Eastern Mediterranean Region: Time to get better data to guide better preparedness. J Infect Public Health 2020; 13:375-376. [PMID: 32164979 DOI: 10.1016/j.jiph.2020.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
| | - Huma Qureshi
- Pakistan Health Research Council, Islamabad, Pakistan
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Nishisaka-Nonaka R, Mawatari K, Yamamoto T, Kojima M, Shimohata T, Uebanso T, Nakahashi M, Emoto T, Akutagawa M, Kinouchi Y, Wada T, Okamoto M, Ito H, Yoshida KI, Daidoji T, Nakaya T, Takahashi A. Irradiation by ultraviolet light-emitting diodes inactivates influenza a viruses by inhibiting replication and transcription of viral RNA in host cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 189:193-200. [PMID: 30391908 DOI: 10.1016/j.jphotobiol.2018.10.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 10/11/2018] [Accepted: 10/18/2018] [Indexed: 10/28/2022]
Abstract
Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock, especially poultry and pigs. This study aimed to investigate how to inactivate IAVs by using different ultraviolet-light-emitting diodes (UV-LEDs). We developed sterilization equipment with light-emitting diodes (LEDs) those peak wavelengths were 365 nm (UVA-LED), 310 nm (UVB-LED), and 280 nm (UVC-LED). These UV-LED irradiations decreased dose fluence-dependent plaque-forming units of IAV H1N1 subtype (A/Puerto Rico/8/1934) infected Madin-Darby canine kidney (MDCK) cells, but the inactivation efficiency of UVA-LED was significantly lower than UVB- and UVC-LED. UV-LED irradiations did not alter hemagglutination titer, but decreased accumulation of intracellular total viral RNA in infected MDCK cells was observed. Additionally, UV-LED irradiations suppressed the accumulation of intracellular mRNA (messenger RNA), vRNA (viral RNA), and cRNA (complementary RNA), as measured by strand-specific RT-PCR. These results suggest that UV-LEDs inhibit host cell replication and transcription of viral RNA. Both UVB- and UVC-LED irradiation decreased focus-forming unit (FFU) of H5N1 subtype (A/Crow/Kyoto/53/2004), a highly pathogenic avian IAV (HPAI), in infected MDCK cells, and the amount of FFU were lower than the H1N1 subtype. From these results, it appears that IAVs may have different sensitivity among the subtypes, and UVB- and UVC-LED may be suitable for HPAI virus inactivation.
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Affiliation(s)
- Risa Nishisaka-Nonaka
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan
| | - Kazuaki Mawatari
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan.
| | - Tomomi Yamamoto
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan
| | - Mizuki Kojima
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan
| | - Takaaki Shimohata
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan
| | - Takashi Uebanso
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan
| | - Mutsumi Nakahashi
- Graduate School of Bioscience and Bioindustry, Tokushima University, Minamijyousanjima-cho 2-1, Tokushima City, Tokushima 770-8506, Japan
| | - Takahiro Emoto
- Graduate School of Science and Technology, Tokushima University, Minamijyousanjima-cho 2-1, Tokushima City, Tokushima 770-8506, Japan
| | - Masatake Akutagawa
- Graduate School of Science and Technology, Tokushima University, Minamijyousanjima-cho 2-1, Tokushima City, Tokushima 770-8506, Japan
| | - Yohsuke Kinouchi
- Graduate School of Science and Technology, Tokushima University, Minamijyousanjima-cho 2-1, Tokushima City, Tokushima 770-8506, Japan
| | - Takahiro Wada
- Nihon Funen Co., Ltd, 179-1 Mitsujima-shinden, Kawashima-cho, Yoshinogawa City, Tokushima 779-3394, Japan
| | - Masayuki Okamoto
- Nihon Funen Co., Ltd, 179-1 Mitsujima-shinden, Kawashima-cho, Yoshinogawa City, Tokushima 779-3394, Japan
| | - Hiroshi Ito
- Nihon Funen Co., Ltd, 179-1 Mitsujima-shinden, Kawashima-cho, Yoshinogawa City, Tokushima 779-3394, Japan
| | - Ken-Ichi Yoshida
- Nihon Funen Co., Ltd, 179-1 Mitsujima-shinden, Kawashima-cho, Yoshinogawa City, Tokushima 779-3394, Japan
| | - Tomo Daidoji
- Department of Infectious Diseases, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Takaaki Nakaya
- Department of Infectious Diseases, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Akira Takahashi
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Kuramoto-cho 3-18-15, Tokushima City, Tokushima 770-8503, Japan
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Salaheldin AH, Kasbohm E, El-Naggar H, Ulrich R, Scheibner D, Gischke M, Hassan MK, Arafa ASA, Hassan WM, Abd El-Hamid HS, Hafez HM, Veits J, Mettenleiter TC, Abdelwhab EM. Potential Biological and Climatic Factors That Influence the Incidence and Persistence of Highly Pathogenic H5N1 Avian Influenza Virus in Egypt. Front Microbiol 2018; 9:528. [PMID: 29636730 PMCID: PMC5880882 DOI: 10.3389/fmicb.2018.00528] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 03/08/2018] [Indexed: 01/09/2023] Open
Abstract
Highly pathogenic H5N1 avian influenza virus (A/H5N1) of clade 2.2.1 is endemic in poultry in Egypt where the highest number of human infections worldwide was reported. During the last 12 years the Egyptian A/H5N1 evolved into several genotypes. In 2007-2014 vaccinated poultry suffered from antigenic drift variants of clade 2.2.1.1 and in 2014/2015 an unprecedented upsurge of A/H5N1 clade 2.2.1.2 occurred in poultry and humans. Factors contributing to the endemicity or re-emergence of A/H5N1 in poultry in Egypt remain unclear. Here, three potential factors were studied: climatic factors (temperature, relative humidity, and wind speed), biological fitness in vitro, and pathogenicity in domestic Pekin and Muscovy ducks. Statistical analyses using negative binomial regression models indicated that ambient temperature in winter months influenced the spread of A/H5N1 in different geographic areas analyzed in this study. In vitro, at 4 and 56°C 2.2.1.1 and recent 2.2.1.2 viruses were more stable than other viruses used in this study. Further, Pekin ducks were more resistant than Muscovy ducks and the viruses were excreted for up to 2 weeks post-infection assuming a strong role as a reservoir. Taken together, ambient temperature in winter months potentially contributes to increasing outbreaks in some regions in Egypt. Heat stability of clade 2.2.1.1 and recent 2.2.1.2 viruses probably favors their persistence at elevated temperatures. Importantly, asymptomatically infected Pekin ducks may play an important role in the spread of avian and human-like A/H5N1 in Egypt. Therefore, control measures including targeted surveillance and culling of silently infected Pekin ducks should be considered.
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Affiliation(s)
- Ahmed H Salaheldin
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany.,Institute of Poultry Diseases, Free University of Berlin, Berlin, Germany.,Department of Poultry Diseases, Faculty of Veterinary Medicine, Alexandria University, Edfina, Egypt
| | - Elisa Kasbohm
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany.,Institute of Mathematics and Computer Science, University of Greifswald, Greifswald, Germany
| | - Heba El-Naggar
- Veterinary Serum and Vaccine Research Institute, Cairo, Egypt
| | - Reiner Ulrich
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - David Scheibner
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Marcel Gischke
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Mohamed K Hassan
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | - Abdel-Satar A Arafa
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | - Wafaa M Hassan
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | | | - Hafez M Hafez
- Institute of Poultry Diseases, Free University of Berlin, Berlin, Germany
| | - Jutta Veits
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Thomas C Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Elsayed M Abdelwhab
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
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6
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Samir M, Hamed M, Abdallah F, Kinh Nguyen V, Hernandez-Vargas EA, Seehusen F, Baumgärtner W, Hussein A, Ali AAH, Pessler F. An Egyptian HPAI H5N1 isolate from clade 2.2.1.2 is highly pathogenic in an experimentally infected domestic duck breed (Sudani duck). Transbound Emerg Dis 2018; 65:859-873. [PMID: 29363279 DOI: 10.1111/tbed.12816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Indexed: 01/26/2023]
Abstract
The highly pathogenic avian influenza (HPAI) H5N1 viruses continue to cause major problems in poultry and can, although rarely, cause human infection. Being enzootic in domestic poultry, Egyptian isolates are continuously evolving, and novel clades vary in their pathogenicity in avian hosts. Considering the importance of domestic ducks as natural hosts of HPAI H5N1 viruses and their likelihood of physical contact with other avian hosts and humans, it is of utmost importance to characterize the pathogenicity of newly emerged HPAI strains in the domestic duck. The most recently identified Egyptian clade 2.2.1.2 HPAI H5N1 viruses have been isolated from naturally infected pigeons, turkeys and humans. However, essentially nothing is known about their pathogenicity in domestic ducks. We therefore characterized the pathogenicity of an Egyptian HPAI H5N1 isolate A/chicken/Faquos/amn12/2011 (clade 2.2.1.2) in Sudani duck, a domestic duck breed commonly reared in Egypt. While viral transcription (HA mRNA) was highest in lung, heart and kidney peaking between 40 and 48 hpi, lower levels were detected in brain. Weight loss of infected ducks started at 16 hpi and persisted until 120 hpi. The first severe clinical signs were noted by 32 hpi and peaked in severity at 72 and 96 hpi. Haematological analyses showed a decline in total leucocytes, granulocytes, platelets and granulocyte/lymphocyte ratio, but lymphocytosis. Upon necropsy, lesions were obvious in heart, liver, spleen and pancreas and consisted mainly of necrosis and petechial haemorrhage. Histologically, lungs were the most severely affected organs, whereas brain only showed mild neuronal degeneration and gliosis at 48 hpi despite obvious neurological clinical signs. Taken together, our results provide first evidence that this HPAI H5N1 isolate (clade 2.2.1.2) is highly pathogenic to Sudani ducks and highlight the importance of this breed as potential reservoir and disseminator of HPAI strains from this clade.
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Affiliation(s)
- M Samir
- TWINCORE, Center for Experimental and Clinical Infection Research, Hannover, Germany.,Department of Zoonoses, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - M Hamed
- Marsa matrouh branch, Animal Health Research Institute, Dokki, Giza, Egypt
| | - F Abdallah
- Department of Virology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - V Kinh Nguyen
- Systems Medicine of Infectious Diseases, Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - E A Hernandez-Vargas
- Systems Medicine of Infectious Diseases, Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - F Seehusen
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - W Baumgärtner
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - A Hussein
- Department of Avian and Rabbit Medicine, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - A A H Ali
- Department of Virology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - F Pessler
- TWINCORE, Center for Experimental and Clinical Infection Research, Hannover, Germany.,Helmholtz Centre for Infection Research, Braunschweig, Germany
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7
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Chen L, Wang C, Luo J, Li M, Liu H, Zhao N, Huang J, Zhu X, Ma G, Yuan G, He H. Amino Acid Substitution K470R in the Nucleoprotein Increases the Virulence of H5N1 Influenza A Virus in Mammals. Front Microbiol 2017; 8:1308. [PMID: 28744280 PMCID: PMC5504190 DOI: 10.3389/fmicb.2017.01308] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/28/2017] [Indexed: 12/21/2022] Open
Abstract
H5N1 is a highly pathogenic influenza A virus (IAV) and poses a major threat to the public health. The nucleoprotein (NP) has a multiple functions during the viral life cycle, however, the precise role of NP mutants in viral replication and pathogenicity is not completely understood. Here, we attempted to identify five residues in NP that may contribute to viral replication or pathogenicity. Of these, K227R, K229R, and K470R viruses were successfully rescued by reverse genetic, but the K91R and K198R viruses were not viable. A mini-genome assay demonstrated that the NP mutations K91R and K198R significantly decreased the polymerase activity. Moreover, these two mutations resulted in disrupted cellular localization in mammalian cells. Importantly, mutation at position 470 of NP significantly increased its virulence in vitro and in vivo. These findings demonstrated that the NP protein plays a major role in influenza virulence and pathogenicity, which adds to the knowledge of IAV virulence determinants and may benefit IAV surveillance.
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Affiliation(s)
- Lin Chen
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China.,University of the Chinese Academy of SciencesBeijing, China
| | - Chengmin Wang
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China
| | - Jing Luo
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China
| | - Meng Li
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China.,University of the Chinese Academy of SciencesBeijing, China
| | - Huimin Liu
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China.,University of the Chinese Academy of SciencesBeijing, China
| | - Na Zhao
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China.,University of the Chinese Academy of SciencesBeijing, China
| | - Jingjing Huang
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China
| | - Xili Zhu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of ScienceBeijing, China
| | - Guoyao Ma
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China.,University of the Chinese Academy of SciencesBeijing, China
| | - Guohui Yuan
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China
| | - Hongxuan He
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of SciencesBeijing, China
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