title: Agreement between assays of cell-mediated immunity utilizing Mycobacterium bovis-specific antigens for the diagnosis of tuberculosis in African buffaloes (Syncerus caffer).
abstract: We assessed the use of Mycobacterium bovis-specific peptides for the diagnosis of tuberculosis in African buffaloes (Syncerus caffer) by evaluating the agreement between the single intradermal comparative tuberculin test (SICTT), the Bovigam(®) EC (BEC) assay, the Bovigam(®) HP (BHP) assay and two assays utilizing the QuantiFERON(®) TB-Gold (in tube) system employing 20 h (mQFT20 assay) and 30 h (mQFT30 assay) whole blood incubation periods. Of 84 buffaloes, 45% were SICTT-positive, 48% were BEC-positive, 50% were BHP-positive, 37% were mQFT20-positive and 43% were mQFT30-positive. Agreement between the BEC and BHP Bovigam(®) assays was high (κ=0.86, 95% CI 0.75-0.97) and these detected the most test-positive animals suggesting that they were the most sensitive assays. Interferon-gamma release was significantly greater in buffaloes that were test-positive for all tests than in animals with discordant but positive Bovigam(®) results. Agreement between the mQFT assays was equally high (κ=0.88, 95% CI 0.77-0.98); however, all buffaloes with discordant mQFT results (n=6) were mQFT30-positive/mQFT20-negative, including three confirmed M. bovis-infected animals, suggesting that the mQFT30 assay is the more sensitive of the two. Agreements between the two Bovigam(®) and two mQFT assays were moderate, suggesting that in its current format the mQFT assay is less sensitive than either the BEC or the BHP assays.
authors.affiliation: DST/NRF Centre of Excellence for Biomedical TB Research/MRC Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa.
authors.forename: Wynand J
authors.initials: WJ
authors.lastname: Goosen
authors.affiliation: DST/NRF Centre of Excellence for Biomedical TB Research/MRC Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa.
authors.forename: Michele A
authors.initials: MA
authors.lastname: Miller
authors.affiliation: DST/NRF Centre of Excellence for Biomedical TB Research/MRC Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa.
authors.forename: Novel N
authors.initials: NN
authors.lastname: Chegou
authors.affiliation: Ezemvelo KZN Wildlife, P.O. Box 25, Mtubatuba 3935, South Africa.
authors.forename: David
authors.initials: D
authors.lastname: Cooper
authors.affiliation: DST/NRF Centre of Excellence for Biomedical TB Research/MRC Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa.
authors.forename: Robin M
authors.initials: RM
authors.lastname: Warren
authors.affiliation: DST/NRF Centre of Excellence for Biomedical TB Research/MRC Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa.
authors.forename: Paul D
authors.initials: PD
authors.lastname: van Helden
authors.affiliation: DST/NRF Centre of Excellence for Biomedical TB Research/MRC Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa. Electronic address: sparsons@sun.ac.za.
authors.forename: Sven D C
authors.initials: SD
authors.lastname: Parsons
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology*; D002020:Buffaloes; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000097:blood; D009163:Mycobacterium bovis / Q000276:immunology*; D014374:Tuberculin Test / Q000662:veterinary; D014376:Tuberculosis / Q000097:blood / Q000175:diagnosis / Q000276:immunology / Q000662:veterinary*
chemical_list: D000942:Antigens, Bacterial; D007371:Interferon-gamma
keywords: African buffalo; Bovigam(®); Bovine tuberculosis; CFP-10; ESAT-6; Interferon-gamma