title: Cross-protection against influenza virus infection by intranasal administration of M2-based vaccine with chitosan as an adjuvant.
abstract: Influenza vaccines based on conserved antigens could provide cross-protection against infections by multiple subtypes of influenza A virus. Influenza matrix protein 2 (M2) is highly conserved in all influenza A strains. In this study, we deleted the transmembrane domain of the M2 of the avian influenza virus (AIV) A/Chicken/Jiangsu/7/2002 (H9N2) strain to create an M2 without a transmembrane domain, named sM2, which was efficiently expressed in Escherichia coli. The sM2 protein was administered intranasally to mice in combination with chitosan adjuvant three times at an interval of 3 weeks. Three weeks after the last immunization, the mice were challenged with a lethal dose (5 x LD(50)) of A/Chicken/Jiangsu/7/2002 (H9N2) virus, PR8 (H1N1) virus and A/Chicken/Henan/12/2004 (H5N1) virus. The protective immunity of the vaccine was evaluated by determining the survival rates, residual lung virus titers, body weight, and the serum antibody titers of the mice. Nasal administration of 15 microg sM2 in combination with chitosan completely protected mice against the homologous virus and protected 90 and 30% of the mice against the heterologous H1N1 and H5N1 viruses, respectively. The study indicated that the sM2 protein was a candidate antigen for a broad-spectrum influenza virus vaccine and that the adjuvant chitosan improved the efficacy of the sM2 vaccine.
authors.affiliation: State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, Hubei, China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Sui
authors.forename: Quanjiao
authors.initials: Q
authors.lastname: Chen
authors.forename: Rui
authors.initials: R
authors.lastname: Wu
authors.forename: Hongbo
authors.initials: H
authors.lastname: Zhang
authors.forename: Mei
authors.initials: M
authors.lastname: Zheng
authors.forename: Hanzhong
authors.initials: H
authors.lastname: Wang
authors.forename: Ze
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000281:Administration, Intranasal; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001835:Body Weight; D048271:Chitosan / Q000008:administration & dosage*; D056738:Cross Protection; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D015870:Gene Expression; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology; D053127:Influenza A Virus, H9N2 Subtype / Q000235:genetics / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D008168:Lung / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D009976:Orthomyxoviridae Infections / Q000517:prevention & control* / Q000821:virology; D016019:Survival Analysis; D019562:Viral Load; D014763:Viral Matrix Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D000086082:Viroporin Proteins
chemical_list: D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D048271:Chitosan; D007252:Influenza Vaccines; D014763:Viral Matrix Proteins; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins