title: Evaluation of oral immunization with recombinant avian influenza virus HA1 displayed on the Lactococcus lactis surface and combined with the mucosal adjuvant cholera toxin subunit B.
abstract: The development of safe and efficient avian influenza vaccines for human and animal uses is essential for preventing virulent outbreaks and pandemics worldwide. In this study, we constructed a recombinant (pgsA-HA1 gene fusion) Lactococcus lactis strain that expresses and displays the avian influenza virus HA1 antigens on its surface. The vectors were administered by oral delivery with or without the addition of cholera toxin subunit B (CTB). The resulting immune responses were analyzed, and the mice were eventually challenged with lethal doses of H5N1 viruses. Significant titers of hemagglutinin (HA)-specific serum IgG and fecal IgA were detected in the group that also received CTB. Cellular immunities were also shown in both cell proliferation and gamma interferon (IFN-γ) enzyme-linked immunospot (ELISpot) assays. Most importantly, the mice that received the L. lactis pgsA-HA1 strain combined with CTB were completely protected from lethal challenge of the H5N1 virus. These findings support the further development of L. lactis-based avian influenza virus vaccines for human and animal uses.
authors.affiliation: College of Life Science and Food Engineering, Nanchang University, Nanchang 330013, People's Republic of China.
authors.forename: Han
authors.initials: H
authors.lastname: Lei
authors.forename: Zhina
authors.initials: Z
authors.lastname: Sheng
authors.forename: Qian
authors.initials: Q
authors.lastname: Ding
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Wei
authors.forename: Dominic Man-Kit
authors.initials: DM
authors.lastname: Lam
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Xu
mesh_terms: D000276:Adjuvants, Immunologic; D000284:Administration, Oral; D000818:Animals; D000956:Antigens, Viral / Q000235:genetics / Q000627:therapeutic use*; D002772:Cholera Toxin; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000627:therapeutic use*; D013294:Lactococcus lactis / Q000235:genetics*; D051379:Mice; D009976:Orthomyxoviridae Infections / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D000276:Adjuvants, Immunologic; D000956:Antigens, Viral; D007252:Influenza Vaccines; D002772:Cholera Toxin