title: Fluorescence polarization assay for the detection of antibodies to Mycobacterium bovis in bovine sera.
abstract: The performance of a fluorescence polarization assay (FPA) that detects antibodies to Mycobacterium bovis in bovine sera is described. The FPA reported here is a direct binding primary screening assay using a small polypeptide derived from the M. bovis MPB70 protein. A secondary inhibition assay confirms suspect or presumed positive samples. Specificity studies involved five different veterinary laboratories testing 4461 presumed negative bovine samples. FPA specificity was 99.9%. The FPA was used to identify herd status as either M. bovis infected or non-infected. Herd surveillance studies (nine herds) were performed in Mexico and South Africa. The FPA had a specificity of 100% (two negative herds), and correctly identified six of seven infected herds. Finally, sera from 105 slaughter animals that had gross lesions in lymph nodes similar to those seen with bovine tuberculosis were tested by the FPA. Thin sections from the associated formalin-fixed paraffin-embedded samples of lymph nodes were stained using hematoxylin and eosin (H&E) for morphologic examination and using the Ziehl-Neelsen (ZN) method for detection of acid-fast bacilli. Of the 105 animals, 78 were classified as TB suspect based on lesion morphology, 21 were positive by ZN, 9 were positive by FPA and 13 were positive by PCR for the tuberculosis group of Mycobacterium. Among the 21 ZN positives, 11 (52.4%) were PCR positive. Among the 9 FPA positives, 8 (88.9%) were PCR positive. For the 13 PCR positives, 8 (61.5%) were FPA positive and 11 (84.6%) were ZN positives. These results show that use of the FPA for detection of M. bovis infection of cattle has value for bovine disease surveillance programs.
authors.affiliation: Diachemix LLC, 683 E. Center Street Unit H, Grayslake, IL 60030, USA. mickj@diachemix.com
authors.forename: Michael E
authors.initials: ME
authors.lastname: Jolley
authors.forename: Mohammad S
authors.initials: MS
authors.lastname: Nasir
authors.forename: Om P
authors.initials: OP
authors.lastname: Surujballi
authors.forename: Anna
authors.initials: A
authors.lastname: Romanowska
authors.forename: Tomas B
authors.initials: TB
authors.lastname: Renteria
authors.forename: Alfonso
authors.initials: A
authors.lastname: De la Mora
authors.forename: Ailam
authors.initials: A
authors.lastname: Lim
authors.forename: Steven R
authors.initials: SR
authors.lastname: Bolin
authors.forename: Anita L
authors.initials: AL
authors.lastname: Michel
authors.forename: Miladin
authors.initials: M
authors.lastname: Kostovic
authors.forename: Edward C
authors.initials: EC
authors.lastname: Corrigan
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D001426:Bacterial Proteins / Q000276:immunology; D002417:Cattle; D016231:Fluorescence Polarization Immunoassay / Q000379:methods / Q000662:veterinary*; D008198:Lymph Nodes / Q000382:microbiology; D008800:Mexico; D009163:Mycobacterium bovis / Q000276:immunology*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011159:Population Surveillance / Q000379:methods; D012680:Sensitivity and Specificity; D013019:South Africa; D014380:Tuberculosis, Bovine / Q000276:immunology* / Q000382:microbiology
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; C060216:MPB70 protein, Mycobacterium bovis