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.
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.
Koo
Hye Cheong
HC
Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, 99164-7040, USA.
Park
Yong Ho
YH
Ahn
Jongsam
J
Waters
W Ray
WR
Palmer
Mitch V
MV
Hamilton
Mary Jo
MJ
Barrington
George
G
Mosaad
Abdelaziz A
AA
Park
Kun Taek
KT
Jung
Woo Kyung
WK
Hwang
In Yeong
IY
Cho
Sang-Nae
SN
Shin
Sang Jae
SJ
Davis
William C
WC
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*
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