title: Characterisation of novel linear antigen epitopes on North American-type porcine reproductive and respiratory syndrome virus M protein.
abstract: The M protein, encoded by the porcine reproductive and respiratory syndrome virus (PRRSV) ORF6 gene, is considered to be one of the most conserved PRRSV proteins. In recent decades, highly specific monoclonal antibodies (Mabs) have been exploited to provide reliable diagnoses for many diseases. In this study, two different Mab clones targeting the linear epitopes on the PRRSV M protein were generated and characterized. Both Mabs showed binding activity against the native PRRSV virion and recombinant M protein when analyzed by immunofluorescence assay (IFA) and Western blot. The targeted epitope of each Mab was mapped by serial truncation of the M protein to generate overlapping fragments. Fine epitope mapping was then performed using a panel of expressed polypeptides. The polypeptide sequences of the two epitopes recognized by Mabs 1C8 and 3F7 were (3)SSLD(6) and (155)VLGGRKAVK(163), respectively, with the former being a newly identified epitope on the M protein. In both cases, these two epitopes were finely mapped for the first time. Alignments of Mab epitope sequences revealed that the two epitopes on the M protein were highly conserved between the North American-type strains. These Mabs, along with their mapped epitopes, are useful for the development of diagnostic and research tools, including immunofluorescence, ELISA and Western blot.
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agribiotechnology, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.forename: Jiazeng
authors.initials: J
authors.lastname: Chen
authors.forename: Jinmei
authors.initials: J
authors.lastname: Peng
authors.forename: Tongqing
authors.initials: T
authors.lastname: An
authors.forename: Chaoliang
authors.initials: C
authors.lastname: Leng
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
authors.forename: Xin
authors.initials: X
authors.lastname: Guo
authors.forename: Xinna
authors.initials: X
authors.lastname: Ge
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Tian
authors.forename: Hanchun
authors.initials: H
authors.lastname: Yang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D018604:Epitope Mapping; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009656:North America; D019318:Porcine Reproductive and Respiratory Syndrome / Q000821:virology*; D019316:Porcine respiratory and reproductive syndrome virus / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D013552:Swine; D014763:Viral Matrix Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; C525999:M protein, porcine reproductive and respiratory syndrome virus; D014763:Viral Matrix Proteins