TY - JOUR
T1 - Assessment of Mycobacterium tuberculosis OmpATb as a novel antigen for the diagnosis of bovine tuberculosis
AU - Schiller, Irene
AU - Vordermeier, H. Martin
AU - Waters, W. Ray
AU - Palmer, Mitchell
AU - Thacker, Tyler
AU - Whelan, Adam
AU - Hardegger, Roland
AU - Marg-Haufe, Beatrice
AU - Raeber, Alex
AU - Oesch, Bruno
PY - 2009/9/1
Y1 - 2009/9/1
N2 - In the search for better tools to control bovine tuberculosis, the development of diagnostic tests with improved specificity and sensitivity has a high priority. We chose to search for novel immunodiagnostic reagents. In this study, Rv0899 (outer membrane protein A of Mycobacterium tuberculosis [OmpATb]) was evaluated as a stimulation antigen in a gamma interferon (IFN-γ) release assay to diagnose bovine tuberculosis. OmpATb induced IFN-γ responses in cattle experimentally infected with M. bovis as early and as persistently as ESAT-6 and CFP-10, the current lead diagnostic antigens. In naturally infected cattle, OmpATb stimulated IFN-γ production in 22 of 26 animals (85%). Importantly, OmpATb detected a portion of M. bovis-infected cattle which did not respond to ESAT-6 and CFP-10 (five of six cattle). The combined diagnostic sensitivity of OmpATb, ESAT-6, and CFP-10 for a preselected group consisting of naturally infected cattle with an overrepresentation of ESAT-6/CFP-10 nonresponders was 96% (25 of 26 animals). The specificity of OmpATb for uninfected cattle was 100% (27 cattle were tested; 12 of them gave false-positive results with tuberculins). In summary, our results indicate that OmpATb has the potential to enhance the sensitivity of previously described diagnostic tests based on ESAT-6 and CFP-10 and that the combined use of OmpATb, ESAT-6, CFP-10, and other proteins may achieve at least equal sensitivity to that obtained with purified protein derivative, but at a higher specificity. Further studies evaluating the diagnostic performance of OmpATb in combination with other proteins are ongoing.
AB - In the search for better tools to control bovine tuberculosis, the development of diagnostic tests with improved specificity and sensitivity has a high priority. We chose to search for novel immunodiagnostic reagents. In this study, Rv0899 (outer membrane protein A of Mycobacterium tuberculosis [OmpATb]) was evaluated as a stimulation antigen in a gamma interferon (IFN-γ) release assay to diagnose bovine tuberculosis. OmpATb induced IFN-γ responses in cattle experimentally infected with M. bovis as early and as persistently as ESAT-6 and CFP-10, the current lead diagnostic antigens. In naturally infected cattle, OmpATb stimulated IFN-γ production in 22 of 26 animals (85%). Importantly, OmpATb detected a portion of M. bovis-infected cattle which did not respond to ESAT-6 and CFP-10 (five of six cattle). The combined diagnostic sensitivity of OmpATb, ESAT-6, and CFP-10 for a preselected group consisting of naturally infected cattle with an overrepresentation of ESAT-6/CFP-10 nonresponders was 96% (25 of 26 animals). The specificity of OmpATb for uninfected cattle was 100% (27 cattle were tested; 12 of them gave false-positive results with tuberculins). In summary, our results indicate that OmpATb has the potential to enhance the sensitivity of previously described diagnostic tests based on ESAT-6 and CFP-10 and that the combined use of OmpATb, ESAT-6, CFP-10, and other proteins may achieve at least equal sensitivity to that obtained with purified protein derivative, but at a higher specificity. Further studies evaluating the diagnostic performance of OmpATb in combination with other proteins are ongoing.
UR - http://www.scopus.com/inward/record.url?scp=69749087379&partnerID=8YFLogxK
U2 - 10.1128/CVI.00151-09
DO - 10.1128/CVI.00151-09
M3 - Article
C2 - 19587150
AN - SCOPUS:69749087379
SN - 1556-6811
VL - 16
SP - 1314
EP - 1321
JO - Clinical and Vaccine Immunology
JF - Clinical and Vaccine Immunology
IS - 9
ER -
