title: Construction of recombinant baculovirus vaccines for Newcastle disease virus and an assessment of their immunogenicity.
abstract: Newcastle disease (ND) is a lethal avian infectious disease caused by Newcastle disease virus (NDV) which poses a substantial threat to China's poultry industry. Conventional live vaccines against NDV are available, but they can revert to virulent strains and do not protect against mutant strains of the virus. Therefore, there is a critical unmet need for a novel vaccine that is safe, efficacious, and cost effective. Here, we designed novel recombinant baculovirus vaccines expressing the NDV F or HN genes. To optimize antigen expression, we tested the incorporation of multiple regulatory elements including: (1) truncated vesicular stomatitis virus G protein (VSV-GED), (2) woodchuck hepatitis virus post-transcriptional regulatory element (WPRE), (3) inverted terminal repeats (ITRs) of adeno-associated virus (AAV Serotype II), and (4) the cytomegalovirus (CMV) promoter. To test the in vivo efficacy of the viruses, we vaccinated chickens with each construct and characterized the cellular and humoral immune response to challenge with virulent NDV (F48E9). All of the vaccine constructs provided some level of protection (62.5-100% protection). The F-series of vaccines provided a greater degree of protection (87.5-100%) than the HN-series (62.5-87.5%). While all of the vaccines elicited a robust cellular and humoral response subtle differences in efficacy were observed. The combination of the WPRE and VSV-GED regulatory elements enhanced the immune response and increased antigen expression. The ITRs effectively increased the length of time IFN-γ, IL-2, and IL-4 were expressed in the plasma. The F-series elicited higher titers of neutralizing antibody and NDV-specific IgG. The baculovirus system is a promising platform for NDV vaccine development that combines the immunostimulatory benefits of a recombinant virus vector with the non-replicating benefits of a DNA vaccine.
authors.affiliation: Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China.
authors.forename: Jingping
authors.initials: J
authors.lastname: Ge
authors.affiliation: Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China.
authors.forename: Liying
authors.initials: L
authors.lastname: Jin
authors.affiliation: Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China.
authors.forename: Dongni
authors.initials: D
authors.lastname: Gao
authors.affiliation: Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China.
authors.forename: Chengle
authors.initials: C
authors.lastname: Bai
authors.affiliation: Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China. Electronic address: wenxiangp@aliyun.com.cn.
authors.forename: Wenxiang
authors.initials: W
authors.lastname: Ping
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D016367:Baculoviridae / Q000235:genetics*; D002645:Chickens; D003001:Cloning, Molecular; D015707:HN Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D009522:Newcastle disease virus / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D061987:Sf9 Cells; D014614:Vaccines, Synthetic / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D014760:Viral Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D000914:Antibodies, Viral; D015707:HN Protein; D014614:Vaccines, Synthetic; D014760:Viral Fusion Proteins
keywords: Baculovirus expression vector system; F gene; HN gene; Immunogenicity; Newcastle disease virus