title: The Identification and Characterization of Two Novel Epitopes on the Nucleocapsid Protein of the Porcine Epidemic Diarrhea Virus.
abstract: Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that causes severe diarrhea and death, particularly in neonatal piglets. The nucleocapsid protein (N protein) of PEDV presents strong immunogenicity and contributes to the cross-reactivity between PEDV and TGEV. However, the characterization of epitopes on the PEDV N protein remains largely unknown. Here, two monoclonal antibodies (MAbs) specific to the N protein of a PEDV strain, FJzz1/2011, were generated and screened against a partially overlapping library of 24 GST-fusion N protein-truncated constructs. We confirmed that residues 18-133 (designated NEP-D4) and residues 252-262 (designated NEP-D6) were the epitopes targeted by MAbs PN-D4 and PN-D6, respectively. Sequence analysis revealed that these two epitopes were highly conserved among PEDV strains but were significantly different from other members of the Coronavirinae subfamily. Western blot analysis showed that they could be specifically recognized by PEDV antisera but could not be recognized by TGEV hyperimmune antisera. Indirect immunofluorescence (IFA) assays confirmed no cross-reaction between these two MAbs and TGEV. In addition, the freeze-thaw cycle and protease treatment results indicated that NEP-D4 was intrinsically disordered. All these results suggest that these two novel epitopes and their cognate MAbs could serve as the basis for the development of precise diagnostic assays for PEDV.
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Kang
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.|Shanghai Key laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, Shanghai, 200240, P. R. China.
authors.forename: Chun
authors.initials: C
authors.lastname: Xie
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Jianan
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Wenchao
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Deqiang
authors.initials: D
authors.lastname: Yang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Lingxue
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Shen
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.
authors.forename: Fei
authors.initials: F
authors.lastname: Gao
authors.affiliation: Shanghai Key laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, Shanghai, 200240, P. R. China.
authors.forename: Zhibiao
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.|Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, P. R. China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P. R. China.|Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, P. R. China.
authors.forename: Guangzhi
authors.initials: G
authors.lastname: Tong
mesh_terms: D000818:Animals; D058846:Antibodies, Monoclonal, Murine-Derived / Q000276:immunology*; D000914:Antibodies, Viral / Q000276:immunology*; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D051379:Mice; D019590:Nucleocapsid Proteins / Q000235:genetics / Q000276:immunology; D019151:Peptide Library; D053485:Porcine epidemic diarrhea virus / Q000235:genetics / Q000378:metabolism; D013552:Swine
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D000914:Antibodies, Viral; D000939:Epitopes; D019590:Nucleocapsid Proteins; D019151:Peptide Library