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1.
Vet Immunol Immunopathol ; 248: 110419, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35439655

RESUMO

Bovine tuberculosis (bTB) control programs can be improved by combined use of tests for humoral and cell-mediated immune responses targeting multiple biomarkers of Mycobacterium bovis. To further the diagnostic benefits of this approach, we used Dual Path Platform (DPP) technology to test sera from cattle with naturally acquired bTB in the United States (US) and Spain for the presence of M. bovis antigen, IgM and/or IgG antibodies to MPB70/MPB83 fusion antigen in conjunction with tuberculin skin tests (TST) or interferon-gamma release assays (IGRA). When TST was complemented with detection of IgM and IgG antibodies, the diagnostic sensitivity increased from 85.4% to 95.1% in the US and from 64.2% to 81.5% in Spain. Likewise, adding the DPP assays enhanced IGRA diagnostic sensitivity from 82.7% to 93.8% in Spain. Detection of circulating M. bovis antigen showed added value when used in combination with the DPP antibody assays but it was limited when analyzed in the context of TST or IGRA results. Present findings support the benefits of a multi-test approach for the ante-mortem diagnosis of bTB in cattle.


Assuntos
Doenças dos Bovinos , Mycobacterium bovis , Tuberculose Bovina , Algoritmos , Animais , Biomarcadores , Bovinos , Imunoglobulina G , Imunoglobulina M , Teste Tuberculínico/veterinária , Tuberculose Bovina/diagnóstico
2.
Vet Immunol Immunopathol ; 240: 110320, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34479106

RESUMO

Recent studies have demonstrated potential for serologic assays to improve surveillance and control programs for bovine tuberculosis. Due to the animal-to-animal variation of the individual antibody repertoires observed in bovine tuberculosis, it has been suggested that serodiagnostic sensitivity can be maximized by use of multi-antigen cocktails or genetically engineered polyproteins expressing immunodominant B-cell epitopes. In the present study, we designed three novel multiepitope polyproteins named BID109, TB1f, and TB2f, with each construct representing a unique combination of four full-length peptides of Mycobacterium bovis predominantly recognized in bovine tuberculosis. Functional performance of the fusion antigens was evaluated using multi-antigen print immunoassay (MAPIA) and Dual Path Platform (DPP) technology with panels of monoclonal and polyclonal antibodies generated against individual proteins included in the fusion constructs as well as with serum samples from M. bovis-infected and non-infected cattle, American bison, and domestic pigs. It was shown that epitopes of each individual protein were expressed in the fusion antigens and accessible for efficient binding by the respective antibodies. The three fusion antigens demonstrated stronger immunoreactivity in MAPIA than that of single protein antigens. Evaluation of the fusion antigens in DPP assay using serum samples from 125 M. bovis-infected and 57 non-infected cattle showed the best accuracy (∼84 %) for TB2f antigen composed of MPB70, MPB83, CFP10, and Rv2650c proteins. Thus, the study results suggest a potential for the multiepitope polyproteins to improve diagnostic sensitivity of serologic assays for bovine tuberculosis.


Assuntos
Testes Sorológicos , Tuberculose Bovina , Animais , Anticorpos , Antígenos de Bactérias , Bovinos , Epitopos de Linfócito B , Mycobacterium bovis/imunologia , Poliproteínas , Testes Sorológicos/veterinária , Tuberculose Bovina/diagnóstico
3.
Vet Immunol Immunopathol ; 239: 110303, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34314936

RESUMO

Bovine tuberculosis (bTB) control programs can be improved by implementation of advanced ante-mortem testing algorithms. Serodiagnostic methods using traditional blood or blood-derived specimens may benefit from the use of less invasive alternative biological fluids, provided those mirror systemic antibody responses. In the present study, we used Dual Path Platform (DPP) and Multiantigen Print Immunoassay (MAPIA) to compare antibody levels in ten sample types including whole blood (fresh and hemolyzed), plasma (fresh and leftover from Bovigam testing), serum, saliva, broncho-alveolar lavage, urine, diaphragm extract, and bile collected from cattle aerosol-infected with Mycobacterium bovis. High correlation (r = 0.97-0.99) in measurements of IgG antibodies to MPB70/MPB83 fusion antigen by DPP assay was found between all blood-derived specimens, supporting matrix equivalency. Broncho-alveolar lavage and diaphragm extract yielded positive results in all the infected animals tested, showing high correlation with matching serum data (r = 0.94 and r = 0.95, respectively) and suggesting their potential use in antibody assays. Characterized by MAPIA, the antigen reactivity patterns obtained with paired sera and alternative specimens were nearly identical, with slight differences in intensity. Antibodies were also found by DPP assay in saliva, urine, and bile from some of the infected animals, but the titers were relatively low, thus reducing the diagnostic value of such specimens. The proposed approach was evaluated in a pilot field study on warthogs diagnosed with M. bovis infection. Relative levels of antibody in tissue fluid obtained from lymph nodes or lungs were consistent with those detected in sera and detectable in all infected warthogs. The findings support the diagnostic utility of non-traditional biological fluids and tissue samples when used as alternative test specimens in serologic assays for bTB.


Assuntos
Anticorpos Antibacterianos/análise , Imunoglobulina G/análise , Doenças dos Suínos , Tuberculose Bovina , Animais , Bovinos , Testes Imunológicos/veterinária , Mycobacterium bovis/imunologia , Extratos Vegetais , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/microbiologia , Tuberculose Bovina/diagnóstico
4.
Comp Immunol Microbiol Infect Dis ; 69: 101424, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31972498

RESUMO

Cattle, bison and buffaloes are susceptible to Mycobacterium bovis, the causative agent for bovine tuberculosis. Accurate and timely identification of infected animals is critical for improved management and control of disease in these species. Bovids develop humoral immune responses to M. bovis infection making serological tests attractive for tuberculosis screening. However, optimization and validation of antibody assays designed for various animal species require understanding of antigen recognition patterns in each target host. The objective of this study was to characterize serological reactivity profiles generated by cattle, American bison, and African buffaloes in tuberculosis. Serum samples from M. bovis-infected animals were tested for the presence of IgM and IgG antibodies to MPB70/MPB83 and CFP10/ESAT6 chimeric proteins using Dual-Path Platform technology. All three host species showed IgG responses of higher magnitude and frequency than IgM responses; further, IgM seroreactivity was limited to MPB70/MPB83, whereas IgG antibodies recognized both test antigens. In cattle, the IgM and IgG responses were elicited mainly by MPB70/MPB83, whereas bison and buffaloes showed similar IgG seroreactivity rates for MPB70/MPB83 and CFP10/ESAT6 antigens. The findings demonstrate distinct patterns of predominant antigen recognition by different bovid species in M. bovis infection.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Interações Hospedeiro-Patógeno/imunologia , Mycobacterium bovis/imunologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Imunoensaio , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia
5.
J Zoo Wildl Med ; 50(4): 1000-1004, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926536

RESUMO

Mycobacterium orygis, a newly identified member of the Mycobacterium tuberculosis complex, has been isolated predominantly from hoofstock in eastern Africa and the Arabian Peninsula, and sporadically in cattle (Bos taurus indicus), rhesus monkeys (Macaca mulatta), humans, and a greater one-horned rhinoceros (Rhinoceros unicornis) in South Asia. In rhinoceros, tuberculosis typically presents as a chronic progressive respiratory disease. The report describes the postmortem diagnosis of tuberculosis caused by Mycobacterium orygis in a greater one-horned rhinoceros with hind limb paresis due to neural granulomatosis. Serologic assays for detection of antibodies to M. tuberculosis complex proteins before culture results allowed for appropriate herd management protocols to be initiated. Mycobacterium genus-specific polymerase chain reaction assays with direct sequencing allowed timely confirmation of the serologic results. This is the first isolation of M. orygis in the western hemisphere, showing the need for mycobacterial testing of rhinoceros before international shipments and the urgency for validated antemortem M. tuberculosis complex screening assays in rhinoceros species.


Assuntos
Mycobacterium/isolamento & purificação , Perissodáctilos/microbiologia , Tuberculose da Coluna Vertebral/veterinária , Animais , Animais de Zoológico , Masculino , Nitrilas , Triazinas , Tuberculose da Coluna Vertebral/epidemiologia , Tuberculose da Coluna Vertebral/microbiologia , Tuberculose da Coluna Vertebral/patologia , Estados Unidos/epidemiologia
6.
Front Vet Sci ; 6: 18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30788347

RESUMO

Tuberculosis (TB) in humans is a global public health concern and the discovery of animal cases of Mycobacterium tuberculosis (Mtb) infection and disease, especially in multi-host settings, also has significant implications for public health, veterinary disease control, and conservation endeavors. This paper describes a fatal case of Mtb disease in a free-ranging African elephant (Loxodonta africana) in a high human TB burden region. Necropsy revealed extensive granulomatous pneumonia, from which Mtb was isolated and identified as a member of LAM3/F11 lineage; a common lineage found in humans in South Africa. These findings are contextualized within a framework of emerging Mtb disease in wildlife globally and highlights the importance of the One Health paradigm in addressing this anthroponotic threat to wildlife and the zoonotic implications.

7.
Clin Vaccine Immunol ; 24(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28978510

RESUMO

Bovine tuberculosis (TB), caused by Mycobacterium bovis, remains an important zoonotic disease posing a serious threat to livestock and wildlife. The current TB tests relying on cell-mediated and humoral immune responses in cattle have performance limitations. To identify new serodiagnostic markers of bovine TB, we screened a panel of 101 recombinant proteins, including 10 polyepitope fusions, by a multiantigen print immunoassay (MAPIA) with well-characterized serum samples serially collected from cattle with experimental or naturally acquired M. bovis infection. A novel set of 12 seroreactive antigens was established. Evaluation of selected proteins in the dual-path platform (DPP) assay showed that the highest diagnostic accuracy (∼95%) was achieved with a cocktail of five best-performing antigens, thus demonstrating the potential for development of an improved and more practical serodiagnostic test for bovine TB.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Mycobacterium bovis/imunologia , Testes Sorológicos/métodos , Tuberculose Bovina/imunologia , Animais , Bovinos , Imunoensaio/métodos
8.
BMC Vet Res ; 13(1): 164, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592322

RESUMO

BACKGROUND: Bovine tuberculosis (TB) control programs generally rely on the tuberculin skin test (TST) for ante-mortem detection of Mycobacterium bovis-infected cattle. RESULTS: Present findings demonstrate that a rapid antibody test based on Dual-Path Platform (DPP®) technology, when applied 1-3 weeks after TST, detected 9 of 11 and 34 of 52 TST non-reactive yet M. bovis-infected cattle from the US and GB, respectively. The specificity of the assay ranged from 98.9% (n = 92, US) to 96.0% (n = 50, GB) with samples from TB-free herds. Multi-antigen print immunoassay (MAPIA) revealed the presence of antibodies to multiple antigens of M. bovis in sera from TST non-reactors diagnosed with TB. CONCLUSIONS: Thus, use of serologic assays in series with TST can identify a significant number of TST non-reactive tuberculous cattle for more efficient removal from TB-affected herds.


Assuntos
Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Imunoglobulina G/imunologia , Masculino , Mycobacterium bovis/imunologia , Fatores de Tempo , Teste Tuberculínico/veterinária
9.
Clin Vaccine Immunol ; 24(6)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28404571

RESUMO

The presence of circulating antigen in cattle experimentally infected with Mycobacterium bovis was demonstrated using dual-path platform (DPP) technology. The antigen capture immunoassays employed rabbit polyclonal antibody recognizing predominantly M. tuberculosis complex-specific epitopes and were able to detect soluble substances and whole cells of mycobacteria. The antigen found in serum appeared to be mostly bound to IgM, but not to IgG, within the immune complexes formed at early stages of M. bovis infection. The antigen was also detected in bile and urine, indicating possible clearance pathways. The data correlation analyses supported the idea of the role of IgM responses in antigen persistence during M. bovis infection. The antigen was detectable in serum months prior to detectable antibody seroconversion. This proof-of-concept study suggested the potential for improved immunodiagnostics for bovine tuberculosis.


Assuntos
Complexo Antígeno-Anticorpo/sangue , Antígenos de Bactérias/sangue , Imunoglobulina M/sangue , Mycobacterium bovis/imunologia , Testes Sorológicos/métodos , Tuberculose Bovina/diagnóstico , Animais , Antígenos de Bactérias/análise , Bile/microbiologia , Bovinos , Urina/microbiologia
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