title: The efficacy of inactivated West Nile vaccine (WN-VAX) in mice and monkeys.
abstract: BACKGROUND
  West Nile virus (WNV) belonging to the genus Flavivirus of the family Flaviviridae causes nervous system disorder in humans, horses and birds. Licensed WNV vaccines are available for use in horses but not for humans. We previously developed an inactivated West Nile virus vaccine (WN-VAX) using a seed virus from West Nile virus (WNV NY99) that was originally isolated in New York City in 1999. In this study, we report the immunogenicity of WN-VAX in both mice and non-human primates.
  
  
  RESULTS
  The WN-VAX immunized mice showed protection against lethal infection with WNV NY99. The challenge test performed on mice passively immunized with serum from other mice that were previously immunized with WN-VAX confirmed that the neutralizing antibody titers of more than 1log10 protected the passively immunized mice from WNV lethal infection. Furthermore, monkeys (Macaca fascicularis) immunized three times with 2.5 μg, 5 μg or 10 μg/dose of WN-VAX exhibited neutralizing antibodies in their sera with titers of more than 2log10 after the second immunization.
  
  
  CONCLUSIONS
  The WN-VAX was protective in mice both by active and passive immunizations and was immunogenic in monkeys. These results suggest that the vaccine developed in this study may be a potential WNV vaccine candidate for human use.
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. ymuraki@mail.biken.or.jp.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Muraki
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. tfujita@mail.biken.or.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Fujita
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. mmatsuura@mail.biken.or.jp.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Matsuura
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. ifuke@mail.biken.or.jp.
authors.forename: Isao
authors.initials: I
authors.lastname: Fuke
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. smanabe@mail.biken.or.jp.
authors.forename: Sadao
authors.initials: S
authors.lastname: Manabe
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. toishika@mail.biken.or.jp.
authors.forename: Toyokazu
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: Kanonji Institute, The Research Foundation for Microbial diseases of Osaka University, Yahata-cho 2-9-41, Kannonnji City, Kagawa, 768-0061, Japan. yokuno@mail.biken.or.jp.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Okuno
authors.affiliation: Department of Virology, Institute of Tropical Medicine, Nagasaki University, Sakamoto-machi 1-12-4, Nagasaki City, Nagasaki, 852-8523, Japan. moritak@nagasaki-u.ac.jp.
authors.forename: Kouichi
authors.initials: K
authors.lastname: Morita
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood / Q000276:immunology; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D004195:Disease Models, Animal; D000882:Haplorhini; D007114:Immunization; D051379:Mice; D009500:Neutralization Tests; D015164:Vaccines, Inactivated / Q000276:immunology*; D014901:West Nile Fever / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D053060:West Nile Virus Vaccines / Q000276:immunology*; D014902:West Nile virus / Q000276:immunology*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D015164:Vaccines, Inactivated; D053060:West Nile Virus Vaccines