title: Mapping of two antigenic domains on the NS3 protein of the pestivirus bovine viral diarrhea virus.
abstract: The immunodominant NS3 (p80) protein of the pestivirus bovine viral diarrhea virus (BVDV) functions as a serine protease and a RNA helicase. To identify antigenic domains of the BVDV NS3, a panel of monoclonal antibodies (mAbs) was tested against fragments of the protein expressed in E. coli. Two large overlapping NS3 fragments, A (amino acids [aa] 1-434) and B (aa 368-683) which together contain all NS3 sequences, were used to screen mAbs for reactivity. Two mAbs, 21.5.8 and 1.11.3, were reactive to fragment A (in ELISA only) and one mAb, 20.10.6, was reactive to fragment B (in ELISA and Western blotting). Further mapping demonstrated that the smallest fragment mAbs 21.5.8 and 1.11.3 bound to was comprised of aa 205-369 (domain A). In Western blotting, the smallest fragment reactive with mAb 20.10.6 was comprised of aa 368-549 (domain B). However, in indirect ELISA, mAb 20.10.6 also demonstrated high reactivity to a smaller fragment comprising aa 368-512 (domain B'). This indicated that the epitope of mAb 20.10.6 was conformational and not linear. Blocking ELISAs using these mAbs and type 1 and type 2 BVDV antisera demonstrated that an immunodominant region of the NS3 protein in cattle is defined by aa 205-549.
authors.affiliation: Lethbridge Laboratory (Animal Diseases Research Institute), Canadian Food Inspection Agency, P.O. Box 640, Lethbridge, Alta., Canada T1J 3Z4. deregtd@inspection.gc.ca
authors.forename: Dirk
authors.initials: D
authors.lastname: Deregt
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Dubovi
authors.forename: Michael E
authors.initials: ME
authors.lastname: Jolley
authors.forename: Phuong
authors.initials: P
authors.lastname: Nguyen
authors.forename: Kimberley M
authors.initials: KM
authors.lastname: Burton
authors.forename: Scott A
authors.initials: SA
authors.lastname: Gilbert
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral / Q000276:immunology; D000956:Antigens, Viral; D002417:Cattle; D001908:Diarrhea Viruses, Bovine Viral / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D016056:Immunodominant Epitopes / Q000032:analysis / Q000276:immunology*; D051379:Mice; D010447:Peptide Hydrolases / Q000276:immunology*; D020365:RNA Helicases / Q000276:immunology*; D017361:Viral Nonstructural Proteins / Q000276:immunology*; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000956:Antigens, Viral; D016056:Immunodominant Epitopes; D010447:Peptide Hydrolases; D020365:RNA Helicases; D017361:Viral Nonstructural Proteins; C086730:p80 protein, bovine viral diarrhea virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases