Abstract
Avian influenza A virus (AIV) is commonly isolated from domestic poultry and wild migratory birds, and the H9N2 subtype is the most prevalent and the major cause of severe disease in poultry in Korea. In addition to the veterinary concerns regarding the H9N2 subtype, it is also considered to be the next potential human pandemic strain due to its rapid evolution and interspecies transmission. In this study, we utilize serial lung-to-lung passage of a low pathogenic avian influenza virus (LPAI) H9N2 (A/Ck/Korea/163/04, WT163) (Y439-lineage) in mice to increase pathogenicity and investigate the potential virulence marker. Mouse-adapted H9N2 virus obtained high virulence (100% mortality) in mice after 98 serial passages. Sequence results show that the mouse adaptation (ma163) possesses several mutations within seven gene segments (PB2, PA, HA, NP, NA, M, and NS) relative to the wild-type strain. The HA gene showed the most mutations (at least 11) with one resulting in the loss of an N-glycosylation site (at amino acid 166). Moreover, reverse genetic studies established that an E627K substitution in PB2 and the loss of the N-glycosylation site in the HA protein (aa166) are critical virulence markers in the mouse-adapted H9N2 virus. Thus, these results add to the increasing body of mutational analysis data defining the function of the viral polymerase and HA genes and their roles in mammalian host adaptation. To our knowledge, this is first report of the generation of a mammalian-adapted Korea H9N2 virus (Y493-lineages). Therefore, this study offers valuable insights into the molecular evolution of the LPAI Korean H9N2 in a new host and adds to the current knowledge of the molecular markers associated with increased virulence.
Similar content being viewed by others
Explore related subjects
Discover the latest articles and news from researchers in related subjects, suggested using machine learning.References
Aamir, U., Wernery, U., Ilyushina, N., and Webster, R. 2007. Characterization of avian H9N2 influenza viruses from United Arab Emirates 2000 to 2003. Virology 361, 45–55.
Basler, C.F., García-Sastre, A., and Palese, P. 1999. Mutation of neuraminidase cysteine residues yields temperature-sensitive influenza viruses. J. Virol. 73, 8095–8103.
Bragstad, K., Nielsen, L.P., and Fomsgaard, A. 2008. The evolution of human influenza A viruses from 1999 to 2006: a complete genome study. Virol. J. 5, 40.
Brown, E. 1990. Increased virulence of a mouse-adapted variant of influenza A/FM/1/47 virus is controlled by mutations in genome segments 4, 5, 7, and 8. J. Virol. 64, 4523–4533.
Brown, I.H. 2000. The epidemiology and evolution of influenza viruses in pigs. Vet. Microbiol. 74, 29–46.
Brown, I., Banks, J., Manvell, R., Essen, S., Shell, W., Slomka, M., Londt, B., and Alexander, D. 2005. Recent epidemiology and ecology of influenza A viruses in avian species in Europe and the Middle East. Dev. Biol. 124, 45–50.
Brown, E., Liu, H., Kit, L.C., Baird, S., and Nesrallah, M. 2001. Pattern of mutation in the genome of influenza A virus on adaptation to increased virulence in the mouse lung: identification of functional themes. Proc. Natl. Acad. Sci. USA 98, 6883–6888.
Butt, K., Smith, G.J., Chen, H., Zhang, L., Leung, Y.C., Xu, K., Lim, W., Webster, R.G., Yuen, K., and Peiris, J.M. 2005. Human infection with an avian H9N2 influenza A virus in Hong Kong in 2003. J. Clin. Microbiol. 43, 5760–5767.
Cameron, K., Gregory, V., Banks, J., Brown, I., Alexander, D., Hay, A., and Lin, Y. 2000. H9N2 subtype influenza A viruses in poultry in Pakistan are closely related to the H9N2 viruses responsible for human infection in Hong Kong. Virology 278, 36–41.
Capua, I. and Alexander, D.J. 2004. Avian influenza: recent developments. Avian. Pathol. 33, 393–404.
Choi, J.G., Lee, Y.J., Kim, Y.J., Lee, E.K., Jeong, O.M., Sung, H.W., Kim, J.H., and Kwon, J.H. 2008. An inactivated vaccine to control the current H9N2 low pathogenic avian influenza in Korea. J. Vet. Med. Sci. 9, 67–74.
Choi, Y., Ozaki, H., Webby, R., Webster, R., Peiris, J., Poon, L., Butt, C., Leung, Y., and Guan, Y. 2004. Continuing evolution of H9N2 influenza viruses in Southeastern China. J. Virol. 78, 8609–8614.
Choi, Y.K., Seo, S.H., Kim, J.A., Webby, R.J., and Webster, R.G. 2005. Avian influenza viruses in Korean live poultry markets and their pathogenic potential. Virology 332, 529–537.
De Wit, E., Munster, V.J., van Riel, D., Beyer, W.E., Rimmelzwaan, G.F., Kuiken, T., Osterhaus, A.D., and Fouchier, R.A. 2010. Molecular determinants of adaptation of highly pathogenic avian influenza H7N7 viruses to efficient replication in the human host. J. Virol. 84, 1597–1606.
Gabriel, G., Dauber, B., Wolff, T., Planz, O., Klenk, H.D., and Stech, J. 2005. The viral polymerase mediates adaptation of an avian influenza virus to a mammalian host. Proc. Natl. Acad. Sci. USA 102, 18590–18595.
Gao, P., Watanabe, S., Ito, T., Goto, H., Wells, K., McGregor, M., Cooley, A.J., and Kawaoka, Y. 1999. Biological heterogeneity, including systemic replication in mice, of H5N1 influenza A virus isolates from humans in Hong Kong. J. Virol. 73, 3184–3189.
Gubareva, L.V., Robinson, M.J., Bethell, R.C., and Webster, R.G. 1997. Catalytic and framework mutations in the neuraminidase active site of influenza viruses that are resistant to 4-guanidino-Neu5Ac2en. J. Virol. 71, 3385–3390.
Guo, Y., Krauss, S., Senne, D., Mo, I., Lo, K., Xiong, X., Norwood, M., Shortridge, K., Webster, R., and Guan, Y. 2000. Characterization of the pathogenicity of members of the newly established H9N2 influenza virus lineages in Asia. Virology 267, 279–288.
Guo, Y., Li, J., and Cheng, X. 1999. Discovery of men infected by avian influenza A (H9N2) virus. Chin. J. Exp. Clin. Virol. 13, 105–108.
Hatta, M. and Kawaoka, Y. 2003. The NB protein of influenza B virus is not necessary for virus replication in vitro. J. Virol. 77, 6050–6054.
Hatta, M. and Kawaoka, Y. 2005. Clue to the molecular mechanism of virulence of highly pathogenic H5N1 avian influenza viruses isolated in 2004. Uirusu 55, 55–61.
Hoffmann, E., Neumann, G., Kawaoka, Y., Hobom, G., and Webster, R.G. 2000. A DNA transfection system for generation of influenza A virus from eight plasmids. Proc. Natl. Acad. Sci. USA 97, 6108–6113.
Katz, J., Veguilla, V., Belser, J., Maines, T., Van Hoeven, N., Pappas, C., Hancock, K., and Tumpey, T. 2009. The public health impact of avian influenza viruses. Poultry Sci. 88, 872–879.
Lee, C.W., Lee, Y.J., Senne, D.A., and Suarez, D.L. 2006. Pathogenic potential of North American H7N2 avian influenza virus: a mutagenesis study using reverse genetics. Virology 353, 388–395.
Lee, C.W., Song, C.S., Lee, Y.J., Mo, I.P., Garcia, M., Suarez, D.L., and Kim, S.J. 2000. Sequence analysis of the hemagglutinin gene of H9N2 Korean avian influenza viruses and assessment of the pathogenic potential of isolate MS96. Avian Dis. 44, 527–535.
Lin, Y., Shaw, M., Gregory, V., Cameron, K., Lim, W., Klimov, A., Subbarao, K., Guan, Y., Krauss, S., and Shortridge, K. 2000. Avianto-human transmission of H9N2 subtype influenza A viruses: relationship between H9N2 and H5N1 human isolates. Proc. Natl. Acad. Sci. USA 97, 9654–9658.
Lipatov, A., Gitelman, A., Govorkova, E., and Smirnov, Y. 1995. Changes of morphological, biological and antigenic properties of avian influenza A virus haemagglutinin H2 in the course of adaptation to new host. Acta Virol. 39, 279–281.
Liu, J., Okazaki, K., Ozaki, H., Sakoda, Y., Wu, Q., Chen, F., and Kida, H. 2003a. H9N2 influenza viruses prevalent in poultry in China are phylogenetically distinct from A/quail/Hong Kongl/G1/97 presumed to be the donor of the internal protein genes of the H5N1 Hong Kong/97 virus. Avian Pathol. 32, 551–560.
Liu, J., Shi, W., Wu, Q., and Guo, Y. 2003b. Sequence analysis of NS1 gene of some H9N2 subtype influenza viruses isolated from chickens in China. Acta Microbiol. Sin. 43, 547–553.
Mase, M., Eto, M., Imai, K., Tsukamoto, K., and Yamaguchi, S. 2007. Characterization of H9N2 influenza A viruses isolated from chicken products imported into Japan from China. Epidemiol. Infect. 135, 386–391.
Mo, I., Brugh, M., Fletcher, O., Rowland, G., and Swayne, D. 1997. Comparative pathology of chickens experimentally inoculated with avian influenza viruses of low and high pathogenicity. Avian Dis. 41, 125–136.
Naeem, K., Ullah, A., Manvell, R., and Alexander, D. 1999. Avian influenza A subtype H9N2 in poultry in Pakistan. Vet. Rec. 145, 560–560.
Narasaraju, T., Sim, M., Ng, H., Phoon, M., Shanker, N., Lal, S., and Chow, V.T. 2009. Adaptation of human influenza H3N2 virus in a mouse pneumonitis model: insights into viral virulence, tissue tropism and host pathogenesis. Microb. Infect. 11, 2–11.
Park, K.J., Kwon, H.I., Song, M.S., Pascua, P.N.Q., Baek, Y.H., Lee, J.H., Jang, H.L., Lim, J.Y., Mo, I.P., and Moon, H.J. 2011. Rapid evolution of low-pathogenic H9N2 avian influenza viruses following poultry vaccination programmes. J. Gen. Virol. 92, 36–50.
Peiris, M., Yuen, K., Leung, C., Chan, K., Ip, P., Lai, R., Orr, W., and Shortridge, K. 1999. Human infection with influenza H9N2. Lancet 354, 916–917.
Reed, L.J. and Muench, H. 1938. A simple method of estimating fifty percent endpoints. Am. J. Epidemiol. 27, 493–497.
Saito, T., Lim, W., Suzuki, T., Suzuki, Y., Kida, H., Nishimura, S.I., and Tashiro, M. 2001. Characterization of a human H9N2 influenza virus isolated in Hong Kong. Vaccine 20, 125–133.
Shinya, K., Hamm, S., Hatta, M., Ito, H., Ito, T., and Kawaoka, Y. 2004. PB2 amino acid at position 627 affects replicative efficiency, but not cell tropism, of Hong Kong H5N1 influenza A viruses in mice. Virology 320, 258–266.
Smee, D.F., Wandersee, M.K., Checketts, M.B., O’Keefe, B.R., Saucedo, C., Boyd, M.R., Mishin, V.P., and Gubareva, L.V. 2007. Influenza A (H1N1) virus resistance to cyanovirin-N arises naturally during adaptation to mice and by passage in cell culture in the presence of the inhibitor. Antivir. Chem. Chemother. 18, 317–327.
Smeenk, C.A. and Brown, E.G. 1994. The influenza virus variant A/FM/1/47-MA possesses single amino acid replacements in the hemagglutinin, controlling virulence, and in the matrix protein, controlling virulence as well as growth. J. Virol. 68, 530–534.
Song, M.S., Pascua, P.N.Q., Lee, J.H., Baek, Y.H., Lee, O.J., Kim, C.J., Kim, H., Webby, R.J., Webster, R.G., and Choi, Y.K. 2009. The polymerase acidic protein gene of influenza A virus contributes to pathogenicity in a mouse model. J. Virol. 83, 12325–12335.
Uyeki, T.M., Chong, Y.H., Katz, J.M., Lim, W., Ho, Y.Y., Wang, S.S., Tsang, T., Au, W., Chan, S.C., and Rowe, T. 2002. Lack of evidence for human-to-human transmission of avian influenza A (H9N2) viruses in Hong Kong, China, 1999. Emerg. Infect. Dis. 8, 154–159.
Wu, S.H., Shu, Y.L., Zhao, Z., Yao, W.Q., Yu, W., Zhang, M.M., Cui, J.Q., Liu, M., Fu, R.H., and Zhao, X.G. 2009. An analysis on genetic characterization of HA1 gene of influenza virus subtype H3N2 circulated from 2001 to 2006 in Liaoning local area. Chin. J. Exp. Clin. Virol. 23, 174–176.
Yamada, S., Hatta, M., Staker, B.L., Watanabe, S., Imai, M., Shinya, K., SakaiTagawa, Y., Ito, M., Ozawa, M., and Watanabe, T. 2010. Biological and structural characterization of a host-adapting amino acid in influenza virus. PLoS Pathog. 6, e1001034.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Park, K.J., Song, MS., Kim, EH. et al. Molecular characterization of mammalian-adapted Korean-type avian H9N2 virus and evaluation of its virulence in mice. J Microbiol. 53, 570–577 (2015). https://doi.org/10.1007/s12275-015-5329-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12275-015-5329-4


