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Assessment of tuberculosis biomarkers in paratuberculosis-infected cattle Полный текст
2023
Klepp, Laura Ines | Colombatti Olivieri, Maria Alejandra | Moyano, Roberto Damian | Romano, Maria Isabel | Malovrh, Tadej | Ocepek, Matjaž | Blanco, Federico Carlos | Bigi, Fabiana
Assessment of tuberculosis biomarkers in paratuberculosis-infected cattle Полный текст
2023
Klepp, Laura Ines | Colombatti Olivieri, Maria Alejandra | Moyano, Roberto Damian | Romano, Maria Isabel | Malovrh, Tadej | Ocepek, Matjaž | Blanco, Federico Carlos | Bigi, Fabiana
Introduction: Mycobacterium bovis and Mycobacterium avium subsp. paratuberculosis, respectively the causative agents of bovine tuberculosis (bTB) and bovine paratuberculosis (PTB), share a high number of antigenic proteins. This characteristics makes the differential diagnosis of the diseases difficult. The interferon gamma (IFN-γ), C-X-C motif chemokine ligand 10 (CXCL10), matrix metallopeptidase 9 (MMP9), interleukin 22 (IL-22) and thrombospondin 1 (THBS1) bovine genes have already been shown to be accurate transcriptional biomarkers of bTB. In order to improve the diagnosis of bTB and PTB, in the present study we evaluated the risk of false positivity of these bTB biomarkers in cattle with PTB. Material and methods: The transcription of these genes was studied in 13 PTB-infected cattle, using Mycobacterium avium subsp. paratuberculosis (MAP)-stimulated peripheral blood mononuclear cells (PBMC). Results: Overall, the levels of IFN-γ, CXCL10, MMP9 and IL-22 transcripts in MAP-stimulated PBMC failed to differentiate animals with PTB from healthy animals. However, as bTB-afflicted cattle do, the MAP-infected group also displayed a lower level of THBS1 transcription than the non-infected animals. Conclusion: The results of this study add new specificity attributes to the levels of transcription of IFN-γ, CXCL10, MMP9 and IL-22 as biomarkers for bTB. | Instituto de Biotecnología | Fil: Klepp, Laura Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina | Fil: Klepp, Laura Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Colombatti Olivieri, Maria Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina | Fil: Colombatti Olivieri, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Moyano, Roberto Damian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina | Fil: Moyano, Roberto Damian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Romano, Maria Isabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina | Fil: Romano, Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Malovrh, Tadej. University of Ljubljana. Veterinary Faculty. Institute for Microbiology and Parasitology; Eslovenia | Fil: Ocepek, Matjaž. University of Ljubljana. Veterinary Faculty. Institute for Microbiology and Parasitology; Eslovenia | Fil: Blanco, Federico Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina | Fil: Blanco, Federico Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Bigi, Fabiana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina | Fil: Bigi, Fabiana. Consejo Nacional de investigaciones Científicas y Tecnológicas; Argentina
Показать больше [+] Меньше [-]Assessment of tuberculosis biomarkers in paratuberculosis-infected cattle Полный текст
2023
Klepp Laura I. | Colombatti María A. | Moyano Roberto D. | Romano María I. | Malovrh Tadej | Ocepek Matjaž | Blanco Federico C. | Bigi Fabiana
Mycobacterium bovis and Mycobacterium avium subsp. paratuberculosis, respectively the causative agents of bovine tuberculosis (bTB) and bovine paratuberculosis (PTB), share a high number of antigenic proteins. This characteristics makes the differential diagnosis of the diseases difficult. The interferon gamma (IFN-γ), C-X-C motif chemokine ligand 10 (CXCL10), matrix metallopeptidase 9 (MMP9), interleukin 22 (IL-22) and thrombospondin 1 (THBS1) bovine genes have already been shown to be accurate transcriptional biomarkers of bTB. In order to improve the diagnosis of bTB and PTB, in the present study we evaluated the risk of false positivity of these bTB biomarkers in cattle with PTB.
Показать больше [+] Меньше [-]Effect of delayed exposure of cattle to Mycobacterium avium subsp paratuberculosis on the development of subclinical and clinical Johne's disease Полный текст
2013
Espejo, Luis A. | Kubat, Noel | Godden, Sandra M. | Wells, Scott J.
Objective—To evaluate the effect of delayed exposure of dairy cattle to Mycobacterium avium subsp paratuberculosis (MAP) on the incidence of those cows testing positive for MAP and developing clinical Johne's disease (CJD). Animals—79 cows not exposed to MAP as calves (unexposed cohort) and 260 cows exposed to MAP as calves (exposed cohort). Procedures—Cows in the unexposed cohort were born into 5 MAP-uninfected herds and introduced at various ages into 5 MAP-infected herds where the exposed cohort cows were born and raised. Beginning when each cow was 24 months old, fecal and serum samples were collected annually from 2003 through 2006. Feces were cultured for MAP, and an ELISA was used to analyze serum samples for antibodies against MAP. Date and reason for culling were obtained from herd records. Incidence of positive culture and ELISA results and CJD was compared between unexposed and exposed cohort cows with Cox regression. Results—Compared with exposed cohort cows, the hazard ratios for unexposed cohort cows having positive culture results, having positive ELISA results, and developing CJD were 0.12, 0.03, and 0.001, respectively, and those ratios increased by 2%, 6%, and 17%, respectively, for each month spent in an MAP-infected herd. Conclusions and Clinical Relevance—Delayed exposure of cows to MAP resulted in lower incidences of positive culture and ELISA results and CJD in those cows, compared with incidences of cows exposed to MAP since birth. The hazard of testing positive for MAP or developing CJD increased with time, regardless of cohort.
Показать больше [+] Меньше [-]Evaluation of an alternative method of herd classification for infection with paratuberculosis in cattle herds in the United States Полный текст
2012
Tavornpanich, Saraya | Wells, Scott J. | Fossler, Charles P. | Roussel, Allen J. | Gardner, Ian A.
Objective: To develop a better system for classification of herd infection status for paratuberculosis (Johne's disease [JD]) in US cattle herds on the basis of the risk of potential transmission of Mycobacterium avium subsp paratubeculosis. Sample: Simulated data for herd size and within-herd prevalence; sensitivity and specificity for test methods obtained from consensus-based estimates. Procedures: Interrelationships among variables influencing interpretation and classification of herd infection status for JD were evaluated by use of simulated data for various herd sizes, true within-herd prevalences, and sampling and testing methods. The probability of finding ≥ 1 infected animal in herds was estimated for various testing methods and sample sizes by use of hypergeometric random sampling. Results: 2 main components were required for the new herd JD classification system: the probability of detection of infection determined on the basis of test results from a sample of animals and the maximum detected number of animals with positive test results. Tables were constructed of the estimated probability of detection of infection, and the maximum number of cattle with positive test results or fecal pools with positive culture results with 95% confidence for classification of herd JD infection status were plotted. Herd risk for JD was categorized on the basis of 95% confidence that the true within-herd prevalence was ≤ 15%, ≤ 10%, ≤ 5%, or ≤ 2%. Conclusions and Clinical Relevance: Analysis of the findings indicated that a scientifically rigorous and transparent herd classification system for JD in cattle is feasible.
Показать больше [+] Меньше [-]Isolation of Mycobacterium paratuberculosis from colostrum and milk of subclinically infected cows
1995
Streeter, R.N. | Hoffsis, G.F. | Bech-Nielsen, S. | Shulaw, W.P. | Rings, D.M.
Mycobacterial culture was performed on colostrum, milk, and feces from 126 clinically normal cows of a single herd with high prevalence of Mycobacterium paratuberculosis infection. Thirty-six (28.6 degrees h) cows were determined to be shedding the organism in the feces. Of the 36 fecal culture-positive cows, M paratuberculosis was isolated from the colostrum of 8 (22.2%) and from the milk of 3 (8.3%). Cows that were heavy fecal shedders were more likely to shed the organism in the colostrum than were light fecal shedders.
Показать больше [+] Меньше [-]Evaluation of an enzyme-linked immunosorbent assay for diagnosis of paratuberculosis in goats
1994
Burnside, D.M. | Rowley, B.O.
A commercial rapid-absorbed ELISA developed to detect antibodies to Mycobacterium paratuberculosis in bovine serum was modified for use with goat serum. Diagnostic sensitivity was evaluated, using a group of 163 goats from a herd with endemic paratuberculosis. Blood and fecal samples were obtained simultaneously, and prevalence of shedding of M paratuberculosis in the feces was estimated by detection of DNA of the mycobacterial insertion sequence, IS900, using a commercial test kit. Diagnostic specificity was evaluated, using blood samples from a total of 123 goats in 10 herds that were considered clinically free of paratuberculosis. The IS900 DNA was detected in 35 of the 163 goats (21%) from the infected herd. Serum antibody to M paratuberculosis was detected in 19 of the 35 IS900 DNA-positive goats, for apparent sensitivity of 54%. Serum antibody was detected in 18 of the 128 IS900 DNA-negative goats from the infected herd. Negative results for serum antibody to M paratuberculosis were obtained for all 123 goats from the herds that were considered clinically free of paratuberculosis.
Показать больше [+] Меньше [-]Isolation of Mycobacterium paratuberculosis from mononuclear cells in tissues, blood, and mammary glands of cows with advanced paratuberculosis
1993
Koenig, G.J. | Hoffsis, G.F. | Shulaw, W.P. | Bech-Nielsen, S. | Rings, D.M. | St-Jean, G.
Seven mature dairy cows from 6 herds were obtained with history, clinical signs of disease, and laboratory findings suggestive of advanced paratuberculosis. A surgically implanted collection chamber was used to obtain peripheral tissue fluid. Blood, mammary gland flush fluid, and collection chamber flush fluid (CCFF) samples were obtained 6 times over a 2-week period from each cow. Mononuclear cell-rich portions of these fluids obtained by gradient centrifugation were submitted for bacteriologic culture of Mycobacterium paratuberculosis and for total and differential cell counts. Bacteriologic culture of feces for M paratuberculosis and complete necropsy performed on each cow at the conclusion of the study confirmed the diagnosis of paratuberculosis. Numbers of tissue macrophages obtained from CCFF samples were lower than expected. Mean (+/- SD) differential count of tissue macrophages collected from CCFF was 65.57 (+/- 23.39). Mean calculated tissue macrophages (total cell count X differential count) collected from CCFF samples was 623.1 (+/- 784.55) cells/microliter. Mycobacterium paratuberculosis was isolated from 1 of 42 (2.4%) collections of mononuclear cell-rich portions of plasma and from 2 of 42 (4.8%) CCFF samples. Mycobacterium paratuberculosis was not isolated from any collections of mammary gland flush fluid. The collection and processing techniques used in this study did not enhance detection of M paratuberculosis infection in cows with advanced paratuberculosis, beyond that of ileocecal lymph node biopsy or fecal culture.
Показать больше [+] Меньше [-]Serodiagnosis of paratuberculosis in sheep by use of agar gel immunodiffusion
1993
Shulaw, W.P. | Bech-Nielsen, S. | Rings, D.M. | Getzy, D.M. | Woodruff, T.S.
An agar gel immunodiffusion (AGID) test was used over a 3-year period to examine 1,871 serum samples from sheep representing 5 Mycobacterium paratuberculosis infected flocks and 4 flocks presumed to be uninfected. Of 1,032 sheep, 31 had positive AGID test results (scoring 1 to 5), and 23 of these 31 were ecropsied. Infection with M paratuberculosis was confirmed by 1 or more of the following findings: observation of typical lesions on histologic examination of sections of ileum or ileocecal lymph nodes, observation of clumps of acid-fast bacteria in mucosal smears of ileum, and isolation of the organism from feces or tissue. False-positive results on AGID testing were not found in sheep from flocks known to have exposure to Cotynebacterium pseudotuberculosis. Diarrhea in infected sheep was observed infrequency; chronic, severe weight loss was the most common sign observed. On histologic examination of tissues from 20 infected sheep, 16 (80%) had diffuse lesions of the ileum and 13 (65%) had acid-fast bacteria in areas of ileal inflammation; 4 had discrete granulomas and peripheral lymphocytic infiltrates in the ileum. Sheep with diffuse lesions tended to have higher mean scores on AGID testing and examination for acid-fast bacteria, compared with those from sheep with more discrete lesions. Bacteriologic culture yielded M paratuberculosis from only 3 sheep with paratuberculosis. On the basis of results of this study, we suggest that the nature of the response to infection with M paratuberculosis may influence the results of diagnostic tests for paratuberculosis, and that AGID testing may be useful to identify M paratuberculosis infection in sheep with chronic weight loss and in flock-screening programs.
Показать больше [+] Меньше [-]Serologic enzyme-linked immunosorbent assay responses of calves vaccinated with a killed Mycobacterium paratuberculosis vaccine
1991
Spangler, E. | Heider, L.E. | Bech-Nielsen, S. | Dorn, C.R.
The purpose of this study was to document the effect of calfhood vaccination for Mycobacterium paratuberculosis on a serologic ELISA. Fifteen calves vaccinated with a killed paratuberculosis vaccine and 5 unvaccinated control calves were tested from the first through the fifteenth month of life. Age of vaccination ranged from 5 to 40 days. Blood samples were collected prior to vaccination and periodically thereafter. Serum antibody was analyzed by use of the ELISA. All calves were Elisa-negative prior to vaccination. Thirteen of 15 vaccinated calves became ELISA-positive between 2 and 6 months after vaccination. The unvaccinated cohort remained Elisa-negative. Widespread use of vaccine may interfere with diagnosis of paratuberculosis and with control programs that are based on serologic tests that measure humoral antibody.
Показать больше [+] Меньше [-]Comparison of the complement-fixation and agar gel immunodiffusion tests for diagnosis of subclinical bovine paratuberculosis
1990
Sherman, D.M. | Gay, J.M. | Bouley, D.S. | Nelson, G.H.
The performance of the serum complement fixation (CF) test was compared with that of a serum agar gel immunodiffusion (AGID) test on 74 subclinically infected and 154 uninfected cattle in 6 commercial midwestern dairy herds with Mycobacterium paratuberculosis infection and on 30 cattle in a herd that was free of infection. Infection status of cattle within herds was established by performance of a series of 3 or more fecal cultures and of ileocecal lymph node cultures of culled cattle. In cattle with subclinical infection detected by culturing, the sensitivity estimates of the CF and AGID tests were 10.8% (3.6% SE) and 18.9% (4.5% SE), respectively. In the cattle classified as disease free, the specificity estimates of the CF and AGID tests were 97.4% (1.3% SE) and 99.4% (0.6% SE), respectively. Neither set of estimates was significantly different. Negative test results obtained with the use of either test in apparently normal cattle from suspect herds should be interpreted with caution because both tests suffer from low sensitivities in subclinically infected animals. However, the AGID test may be more useful in regulatory situations in which the CF test is currently used because the AGID test is easier to perform and to interpret.
Показать больше [+] Меньше [-]Comparison of two methods for isolation of Mycobacterium paratuberculosis from bovine fecal samples
1989
Kim, Y.G. | Bech-Nielsen, S. | Gordon, J.C. | Slemons, R.D. | Spangler, E.
Fecal samples from 131 cattle clinically suspect for paratuberculosis were cultured bacteriologically, using the traditional sedimentation processing method and a processing method that included a centrifugation step. Of 16 samples that were contaminated, 6 were culture-positive on at least 1 medium and by 1 processing method. Ten of 131 (7.6%) fecal samples processed by both methods were lost because of contamination. The number of culture-positive samples (using both processing methods) were 65 of 121 (53.7%) on media without miconazole and 60 of 121 (49.6%) on media with miconazole. Seven of the 121 (5.8%) samples were culture-positive, using centrifugation, after 16 weeks' incubation at 37 C. Thirteen of 60 (21.7%) isolates were obtained only with centrifugation, and 10 of these had low colony counts, suggesting that a centrifugation step may have concentrated microorganisms that would have gone undetected without centrifugation. Six of 60 (10%) isolates positive for M paratuberculosis on the sedimentation method were negative on the centrifugation method. Contamination rates were significantly (P less than 0.001) increased when centrifugation was used. The miconazole significantly (P less 0.001) decreased contamination rates when centrifugation was used.
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