title: Use of rMPB70 protein and ESAT-6 peptide as antigens for comparison of the enzyme-linked immunosorbent, immunochromatographic, and latex bead agglutination assays for serodiagnosis of bovine tuberculosis.
abstract: Current assays used to detect Mycobacterium bovis infection lack accuracy, especially for recently infected animals, or are impractical for rapid field diagnostic applications. To overcome these limitations with serological assays, a synthetic peptide derived from early secretory antigenic target 6 (ESAT6-p) and a recombinant major secreted immunogenic protein (rMPB70) of M. bovis were used in an enzyme-linked immunosorbent assay (EIA), an immunochromatographic assay (ICGA), and a latex bead agglutination assay (LBAA). Sera from noninfected, M. bovis-infected, or M. avium subsp. paratuberculosis-infected (by natural and experimental routes) animals were evaluated. Receiver operating characteristic analysis comparing optical density values from the EIA with results of bacterial culture or skin test, the reference test, established suitable cutoff values for assessing sensitivity and specificity. The EIA and LBAA, respectively, had sensitivities of 98.6 and 94.8%, specificities of 98.5 and 92.6%, and kappa values of 0.97 and 0.88 with ESAT6-p. The EIA, ICGA, and LBAA, respectively, had sensitivities of 96.8, 83.0, and 86.7%, specificities of 90.1, 99.4, and 97.8%, and kappa values of 0.87, 0.85, and 0.83 with rMPB70. Examination of serial samples of sera collected from experimentally M. bovis-infected cattle and deer revealed that ESAT6-p-specific responses developed early after infection whereas responses to rMPB70 developed later in the course of disease. The advantage of the LBAA and ICGA as initial tests for multiple species is a rapid reaction obtained in 2 to 3 h by LBAA or 20 min by ICGA without species-specific secondary antibodies under field conditions, thus allowing immediate segregation of suspect animals for further testing before culling.
authors.affiliation: Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, 99164-7040, USA.
authors.forename: Hye Cheong
authors.initials: HC
authors.lastname: Koo
authors.forename: Yong Ho
authors.initials: YH
authors.lastname: Park
authors.forename: Jongsam
authors.initials: J
authors.lastname: Ahn
authors.forename: W Ray
authors.initials: WR
authors.lastname: Waters
authors.forename: Mitch V
authors.initials: MV
authors.lastname: Palmer
authors.forename: Mary Jo
authors.initials: MJ
authors.lastname: Hamilton
authors.forename: George
authors.initials: G
authors.lastname: Barrington
authors.forename: Abdelaziz A
authors.initials: AA
authors.lastname: Mosaad
authors.forename: Kun Taek
authors.initials: KT
authors.lastname: Park
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Jung
authors.forename: In Yeong
authors.initials: IY
authors.lastname: Hwang
authors.forename: Sang-Nae
authors.initials: SN
authors.lastname: Cho
authors.forename: Sang Jae
authors.initials: SJ
authors.lastname: Shin
authors.forename: William C
authors.initials: WC
authors.lastname: Davis
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D002417:Cattle; D002845:Chromatography / Q000379:methods; D003670:Deer; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay; D007841:Latex Fixation Tests; D016927:Mycobacterium avium subsp. paratuberculosis; D009163:Mycobacterium bovis / Q000276:immunology*; D010283:Paratuberculosis / Q000175:diagnosis / Q000382:microbiology; D010455:Peptides / Q000235:genetics / Q000276:immunology*; D011933:Reagent Kits, Diagnostic; D011994:Recombinant Proteins / Q000276:immunology; D012680:Sensitivity and Specificity; D012698:Serologic Tests; D014380:Tuberculosis, Bovine / Q000175:diagnosis*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C093276:ESAT-6 protein, Mycobacterium tuberculosis; D010455:Peptides; D011933:Reagent Kits, Diagnostic; D011994:Recombinant Proteins; C060216:MPB70 protein, Mycobacterium bovis