title: Immunogenicity of virus-like particles containing modified goose parvovirus VP2 protein.
abstract: The major capsid protein VP2 of goose parvovirus (GPV) expressed using a baculovirus expression system (BES) assembles into virus-like particles (VLPs). To optimize VP2 gene expression in Sf9 cells, we converted wild-type VP2 (VP2) codons into codons that are more common in insect genes. This change greatly increased VP2 protein production in Sf9 cells. The protein generated from the codon-optimized VP2 (optVP2) was detected by immunoblotting and an indirect immunofluorescence assay (IFA). Transmission electron microscopy analysis revealed the formation of VLPs. These findings indicate that optVP2 yielded stable and high-quality VLPs. Immunogenicity assays revealed that the VLPs are highly immunogenic, elicit a high level of neutralizing antibodies and provide protection against lethal challenge. The antibody levels appeared to be directly related to the number of GP-Ag-positive hepatocytes. The variation trends for GP-Ag-positive hepatocytes were similar in the vaccine groups. In comparison with the control group, the optVP2 VLPs groups exhibited obviously better responses. These data indicate that the VLPs retained immunoreactivity and had strong immunogenicity in susceptible geese. Thus, GPV optVP2 appears to be a good candidate for the vaccination of goslings.
authors.affiliation: Division of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai 200241, China.
authors.forename: Zongyan
authors.initials: Z
authors.lastname: Chen
authors.forename: Chuanfeng
authors.initials: C
authors.lastname: Li
authors.forename: Yingqi
authors.initials: Y
authors.lastname: Zhu
authors.forename: Binbin
authors.initials: B
authors.lastname: Wang
authors.forename: Chunchun
authors.initials: C
authors.lastname: Meng
authors.forename: Guangqing
authors.initials: G
authors.lastname: Liu
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D016367:Baculoviridae / Q000235:genetics; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology*; D003062:Codon; D005777:Geese; D015870:Gene Expression; D005822:Genetic Vectors; D046529:Microscopy, Electron, Transmission; D010322:Parvoviridae Infections / Q000517:prevention & control / Q000662:veterinary; D017992:Parvovirus / Q000235:genetics / Q000276:immunology*; D011201:Poultry Diseases / Q000517:prevention & control; D061987:Sf9 Cells; D016019:Survival Analysis; D058425:Vaccines, Virus-Like Particle / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D022701:Virosomes / Q000648:ultrastructure
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D036022:Capsid Proteins; D003062:Codon; D058425:Vaccines, Virus-Like Particle; D022701:Virosomes