Mutant influenza A virus nucleoprotein is preferentially localized in the cytoplasm and its immunization in mice shows higher immunogenicity and cross-reactivity.
Many influenza vaccines targeted to hemagglutinin (HA) show efficient immunogenicity for protecting subjects against influenza virus infection. Major antigenic changes to HA molecules can help influenza virus to develop resistance against HA-targeted vaccines. DNA vaccines encoding conserved antigens protect animals against diverse subtypes, but their potency requires further improvement. We generated a DNA-based nucleoprotein (NP)-targeted vaccine using an N-terminal mutant of NP (NPm) that efficiently localized in the cytoplasm, and examined the immune responses in mice immunized with NPm or wild-type (WT) NP DNA vaccine. Importantly, the NPm vaccine showed 1.5-2-fold higher immunogenicity than the WT NP vaccine in mice. Furthermore, NPm vaccination efficiently protected the mice against lethal challenge with influenza viruses and showed cross-reactivity toward heterologous viruses. Therefore, DNA-based vaccination with NPm may contribute to the development of protective immunity against diverse influenza virus through its ability to stimulate cellular immunity.
Ohba
Kenji
K
Department of Molecular Virology, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. oken818.molv@tmd.ac.jp
Yoshida
Shinsuke
S
Zahidunnabi Dewan
Md
M
Shimura
Hiromi
H
Sakamaki
Nozomi
N
Takeshita
Fumihiko
F
Yamamoto
Naoki
N
Okuda
Kenji
K
D000818:Animals; D003429:Cross Reactions; D003593:Cytoplasm / Q000737:chemistry*; D005434:Flow Cytometry; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology / Q000517:prevention & control*; D007371:Interferon-gamma / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009154:Mutation; D019590:Nucleocapsid Proteins; D009698:Nucleoproteins / Q000032:analysis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*; D014758:Viral Core Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*
D007252:Influenza Vaccines; C048842:NP protein, Influenza A virus; D019590:Nucleocapsid Proteins; D009698:Nucleoproteins; D016601:RNA-Binding Proteins; D019444:Vaccines, DNA; D014758:Viral Core Proteins; D007371:Interferon-gamma