title: Characterization of self-assembled virus-like particles of dromedary camel hepatitis e virus generated by recombinant baculoviruses.
abstract: Dromedary camel hepatitis E virus (DcHEV), a novel hepatitis E virus, has been identified in dromedary camels in Dubai, United Arab Emirates. The antigenicity, pathogenicity and epidemiology of this virus have been unclear. Here we first used a recombinant baculovirus expression system to express the 13 and 111 N-terminus amino-acid-truncated DcHEV ORF2 protein in insect Tn5 cells, and we obtained two types of virus-like particles (VLPs) with densities of 1.300 g/cm(3) and 1.285 g/cm(3), respectively. The small VLPs (Dc4sVLPs) were estimated to be 24 nm in diameter, and were assembled by a protein with the molecular mass 53 kDa. The large VLPs (Dc3nVLPs and Dc4nVLPs) were 35 nm in diameter, and were assembled by a 64-kDa protein. An antigenic analysis demonstrated that DcHEV was cross-reactive with G1, G3-G6, ferret and rat HEVs, and DcHEV showed a stronger cross-reactivity to G1 G3-G6 HEV than it did to rat and ferret HEV. In addition, the antibody against DcHEV-LPs neutralized G1 and G3 HEV in a cell culture system, suggesting that the serotypes of these HEVs are identical. We also found that the amino acid residue Met-358 affects the small DcHEV-LPs assembly.
authors.affiliation: Department of Microbiology, Nanchang Center for Disease Control and Prevention Nanchang, Jiangxi, China.
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Departments of Pathology, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan.
authors.forename: Michiyo
authors.initials: M
authors.lastname: Kataoka
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University, NY, NY 10032, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0781, Japan.
authors.forename: Naokazu
authors.initials: N
authors.lastname: Takeda
authors.affiliation: Departments of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan.
authors.forename: Takaji
authors.initials: T
authors.lastname: Wakita
authors.affiliation: Departments of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan. Electronic address: litc@nih.go.jp.
authors.forename: Tian-Cheng
authors.initials: TC
authors.lastname: Li
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D000956:Antigens, Viral / Q000032:analysis; D016367:Baculoviridae; D002162:Camelus; D002460:Cell Line; D003429:Cross Reactions; D005260:Female; D005289:Ferrets; D005822:Genetic Vectors; D016752:Hepatitis E virus / Q000145:classification / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D007313:Insecta; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D008970:Molecular Weight; D055503:Protein Multimerization; D017208:Rats, Wistar; D017422:Sequence Analysis, DNA; D014479:United Arab Emirates; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D022701:Virosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D000956:Antigens, Viral; D014764:Viral Proteins; D022701:Virosomes
keywords: Dromedary camel HEV; Insect cells Tn5; Recombinant baculovirus; VLP; Virus-like particles