title: Second generation competitive enzyme immunoassay for detection of bovine antibody to Brucella abortus.
abstract: A second generation competitive enzyme immunoassay (CELISA) for detection of bovine antibody to Brucella abortus was developed. This assay was different from previously developed CELISAs in that the detection reagent used was a recombinant combination of the receptor portions of protein A and protein G, labelled with horseradish peroxidase. This eliminates the need for polyclonal anti-mouse-enzyme conjugate reagents for detection thus allowing for true standardization. The assay utilized a monoclonal antibody specific for a common epitope of the O-polysaccharide (OPS) of smooth lipopolysaccharide (SLPS) derived from B. abortus S1119.3 but which did not react with protein A/G. This monoclonal antibody was used to compete with antibody in the bovine test serum. Binding of bovine antibody to the smooth lipopolysaccharide antigen was then measured directly with the protein A/G enzyme conjugate. In this case, development of colour in the reaction was indicative of the presence of bovine antibody. The performance characteristics, sensitivity, specificity and exclusion of B. abortus S19 vaccinated animals, of the assay were very similar to those of the classical CELISA.
authors.affiliation: Canadian Food Inspection Agency, Ottawa Laboratory Fallowfield, 3851 Fallowfield Road, Ottawa, Ontario, Canada K2H 8P9. nielsenk@inspection.gc.ca
authors.forename: K
authors.initials: K
authors.lastname: Nielsen
authors.forename: P
authors.initials: P
authors.lastname: Smith
authors.forename: W L
authors.initials: WL
authors.lastname: Yu
authors.forename: C
authors.initials: C
authors.lastname: Elmgren
authors.forename: P
authors.initials: P
authors.lastname: Nicoletti
authors.forename: B
authors.initials: B
authors.lastname: Perez
authors.forename: R
authors.initials: R
authors.lastname: Bermudez
authors.forename: T
authors.initials: T
authors.lastname: Renteria
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D000911:Antibodies, Monoclonal / Q000097:blood; D000942:Antigens, Bacterial / Q000276:immunology; D001667:Binding, Competitive; D002004:Brucella Vaccine / Q000276:immunology*; D002003:Brucella abortus / Q000276:immunology*; D002007:Brucellosis, Bovine / Q000175:diagnosis* / Q000276:immunology; D002417:Cattle; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards / Q000662:veterinary*; D019081:O Antigens; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014611:Vaccination / Q000662:veterinary
chemical_list: D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D002004:Brucella Vaccine; D019081:O Antigens