Identification of two dominant linear epitopes on the GP3 protein of highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV)

• Published in: Research in veterinary science Vol. 97; no. 2; pp. 238 - 243
• Main Authors: Chen, Jia-zeng, Wang, Qian, Bai, Yun, Wang, Bin, Zhao, Hong-yuan, Peng, Jin-mei, An, Tong-qing, Tian, Zhi-jun, Tong, Guang-zhi
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2014; Elsevier Limited
• Subjects: Amino Acid Sequence; Animals; Antibodies, Viral - blood; Antibodies, Viral - immunology; Antibody purification; Antigens, Viral - immunology; Bacteriology; Chromatography; Cloning; Enzyme-Linked Immunosorbent Assay; Epitope; Epitopes - genetics; Epitopes - immunology; Glycosylation; GP3; Hogs; HP-PRRSV; Molecular Sequence Data; Mutation - genetics; Plasmids; Porcine Reproductive and Respiratory Syndrome - blood; Porcine Reproductive and Respiratory Syndrome - immunology; Porcine respiratory and reproductive syndrome virus; Porcine respiratory and reproductive syndrome virus - genetics; Porcine respiratory and reproductive syndrome virus - immunology; Proteins; Sequence Alignment; Swine; Veterinary medicine; Viral Proteins - genetics; Viral Proteins - immunology; Viral Proteins - metabolism; HP-PRRSV; GP3; Epitope; Antibody purification
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2014.07.011

•Two distinct epitopes were identified in the GP3 of PRRSV.•Their antigenicity is excellent in vivo.•The newly identified epitopes may be useful for diagnosis of PRRS. Glycosylated protein 3 (GP3) of PRRSV is variable between different PRRSV strains, so it is helpful for subtype classifying by using distinct epitopes. In this study, two dominant linear GP3 epitopes that were recognized by highly dilute serum in an enzyme-linked immunosorbent assay (ELISA) were identified. Sequence alignments of 36 North American (NA) PRRSV isolates revealed that the epitope H87DELGFMV94 is well conserved, whereas the epitope T59RQAAAEILE68 differs in other low-virulence NA-type strains, which have at least one amino acid mutation in this region. A mutational analysis revealed that none of these mutations could be recognized by the purified antibodies directed against the corresponding epitope, indicating that the genetic variations altered the antigenicity of the antigenic region. Using ELISA, we also found that antibodies directed against the two epitopes were present in more than 45 of 50 HP-PRRS-positive pig sera, suggesting that their antigenicity is excellent in vivo.