title: H9N2 avian influenza virus-like particle vaccine provides protective immunity and a strategy for the differentiation of infected from vaccinated animals.
abstract: In the present study, virus-like particles (VLPs) were evaluated as a candidate poultry vaccine against avian influenza virus (AIV) subtype H9N2. Specific pathogen-free chickens received a single injection of the VLP vaccine expressing HA and M1 protein of AIV H9N2 (H9 HA VLP) at escalating doses in the presence or absence of ISA70 water-in-oil adjuvant. At 3 weeks post vaccination, we performed hemagglutination inhibition (HI) test and enzyme-linked immunosorbent assay (ELISA) to determine serological immune responses, and challenge studies using SPF chickens. A single dose of H9 HA VLP vaccine induced high levels of HI antibodies and lowered frequencies of virus isolation after the wild-type virus challenge. The addition of ISA70 adjuvant significantly increased the immunogenicity of H9 HA VLP vaccines. Furthermore, it allows differentiation of AIV-infected chickens from vaccinated chickens with an ELISA using nucleocapsid antigen, which offers a promising strategy to differentiate infected from vaccinated animals (DIVA). These results provide support for continued development of the VLP as an animal vaccine against influenza virus.
authors.affiliation: Avian Disease Laboratory, College of Veterinary Medicine, Konkuk University, Gwangjin-gu, Seoul, 143-701, Republic of Korea.
authors.forename: Dong-Hun
authors.initials: DH
authors.lastname: Lee
authors.forename: Jae-Keun
authors.initials: JK
authors.lastname: Park
authors.forename: Yu-Na
authors.initials: YN
authors.lastname: Lee
authors.forename: Jae-Min
authors.initials: JM
authors.lastname: Song
authors.forename: Sang-Moo
authors.initials: SM
authors.lastname: Kang
authors.forename: Joong-Bok
authors.initials: JB
authors.lastname: Lee
authors.forename: Seung-Yong
authors.initials: SY
authors.lastname: Park
authors.forename: In-Soo
authors.initials: IS
authors.lastname: Choi
authors.forename: Chang-Seon
authors.initials: CS
authors.lastname: Song
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D002645:Chickens / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D006385:Hemagglutination Inhibition Tests; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics / Q000276:immunology; D053127:Influenza A Virus, H9N2 Subtype / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification / Q000472:pathogenicity; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D011201:Poultry Diseases / Q000276:immunology / Q000517:prevention & control / Q000821:virology; D013047:Specific Pathogen-Free Organisms; D014611:Vaccination / Q000662:veterinary*; D058425:Vaccines, Virus-Like Particle / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D014763:Viral Matrix Proteins / Q000235:genetics / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; C488936:M1 protein, Influenza A virus; D058425:Vaccines, Virus-Like Particle; D014763:Viral Matrix Proteins; C109963:hemagglutinin, avian influenza A virus