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Chaubey KK, Gupta RD, Gupta S, Singh SV, Bhatia AK, Jayaraman S, Kumar N, Goel A, Rathore AS, Sahzad, Sohal JS, Stephen BJ, Singh M, Goyal M, Dhama K, Derakhshandeh A. Trends and advances in the diagnosis and control of paratuberculosis in domestic livestock. Vet Q 2016; 36:203-227. [PMID: 27356470 DOI: 10.1080/01652176.2016.1196508] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Paratuberculosis (pTB) is a chronic granulomatous enteritis caused by Mycobacterium avium subsp. paratuberculosis (MAP) in a wide variety of domestic and wild animals. Control of pTB is difficult due to the lack of sensitive, efficacious and cost-effective diagnostics and marker vaccines. Microscopy, culture, and PCR have been used for the screening of MAP infection in animals for quite a long time. Besides, giving variable sensitivity and specificity, these tests have not been considered ideal for large-scale screening of domestic livestock. Serological tests like ELISA easily detects anti-MAP antibodies. However, it cannot differentiate between the vaccinated and infected animals. Nanotechnology-based diagnostic tests are underway to improve the sensitivity and specificity. Newer generation diagnostic tests based on recombinant MAP secretory proteins would open new paradigm for the differentiation between infected and vaccinated animals and for early detection of the infection. Due to higher seroreactivity of secretory proteins vis-à-vis cellular proteins, the secretory proteins may be used as marker vaccine, which may aid in the control of pTB infection in animals. Secretory proteins can be potentially used to develop future diagnostics, surveillance and monitoring of the disease progression in animals and the marker vaccine for the control and eradication of pTB.
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Affiliation(s)
- Kundan Kumar Chaubey
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India.,b Department of Microbiology and Immunology , GLA University , Mathura , India
| | - Rinkoo Devi Gupta
- c Department of Life sciences and Biotechnology , South Asian University , New Delhi , India
| | - Saurabh Gupta
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India.,b Department of Microbiology and Immunology , GLA University , Mathura , India
| | - Shoor Vir Singh
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India
| | - Ashok Kumar Bhatia
- b Department of Microbiology and Immunology , GLA University , Mathura , India
| | - Sujata Jayaraman
- d Amity Institutes of Microbial Technology , Amity University , Jaipur , India
| | - Naveen Kumar
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India
| | - Anjana Goel
- b Department of Microbiology and Immunology , GLA University , Mathura , India
| | - Abhishek Singh Rathore
- c Department of Life sciences and Biotechnology , South Asian University , New Delhi , India
| | - Sahzad
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India
| | - Jagdip Singh Sohal
- d Amity Institutes of Microbial Technology , Amity University , Jaipur , India
| | - Bjorn John Stephen
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India
| | - Manju Singh
- a Microbiology Laboratory, Animal Health Division , Central Institute for Research on Goats , Mathura , India
| | - Manish Goyal
- e Division of Parasitology , Central Drug Research Institute , Lucknow , India
| | - Kuldeep Dhama
- f Pathology Division , Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Abdollah Derakhshandeh
- g Department of Pathobiology, School of Veterinary Medicine , Shiraz University , Shiraz , Iran
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Kavid N, Madani R, Hosseinkhani S, Mosavari N, Golchinfar F, Emami T, Keshavarz R. Evaluation of immunogenicity of purified cell wall-associated 34 kDa antigen of Mycobacterium avium subsp. paratuberculosis infection. Hybridoma (Larchmt) 2012; 31:163-7. [PMID: 22741579 DOI: 10.1089/hyb.2011.0108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The 34 kDa cell wall protein of Mycobacterium avium subsp. paratuberculosis (MAP) has been suggested as a major species-specific immunodominant antigen in Johne's disease. However to date, there has not been a purified 34 kDa protein isolated from bacterial lysates used in immunogenicity analysis. Therefore we attempted to assess the immunogenicity properties of the purified cell wall 34 kDa protein for the first time, and compare the results with previous studies. We used an ELISA test for evaluation of the immunogenicity of this 34 kDa antigen against MAP infection. All serum samples from cattle confirmed to be infected with MAP were positive and those from healthy cattle were negative with the present antigen in ELISA tests. The sensitivity and specificity of 34 kDa antigen were then evaluated in comparison with a standard commercial kit and whole cell wall extracts. The results indicated that the pure 34 kDa antigen specific to MAP with high specificity and sensitivity has a strong potential for use in serodiagnosis assays and screening of Johne's disease.
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Affiliation(s)
- Narges Kavid
- Department of Biotechnology, Razi Vaccine and Serum Research Institute, Karadj, Iran
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Mikkelsen H, Aagaard C, Nielsen SS, Jungersen G. Review of Mycobacterium avium subsp. paratuberculosis antigen candidates with diagnostic potential. Vet Microbiol 2011; 152:1-20. [DOI: 10.1016/j.vetmic.2011.03.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 03/02/2011] [Accepted: 03/10/2011] [Indexed: 11/25/2022]
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4
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Santema W, Overdijk M, Barends J, Krijgsveld J, Rutten V, Koets A. Searching for proteins of Mycobacterium avium subspecies paratuberculosis with diagnostic potential by comparative qualitative proteomic analysis of mycobacterial tuberculins. Vet Microbiol 2009; 138:191-6. [PMID: 19349126 DOI: 10.1016/j.vetmic.2009.03.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 03/02/2009] [Accepted: 03/06/2009] [Indexed: 10/21/2022]
Abstract
Accurate immunodiagnosis of bovine paratuberculosis is among others hampered by the lack of specific antigens. One of the most frequently used antigen preparations is purified protein derivative (PPD), also known as tuberculin. This crude extract has limitations when used in diagnostic assays due to the presence of cross-reactive antigens. The aim of the current study was to systematically analyze the qualitative protein composition of PPD of the major mycobacterial pathogens. One-dimensional gel electrophoresis followed by tandem mass spectrometry analysis of PPD from Mycobacterium avium subspecies paratuberculosis (MAP), Mycobacterium avium subspecies avium (MAA) and Mycobacterium bovis (MB) identified 156, 95 and 132 proteins, respectively. Comparative sequence analysis led to the selection of a MAP-specific protein (MAP1718c), and finally heterologous expression in Escherichia coli of this and other diagnostic candidate proteins (MAP3515c and MAP1138c (LprG)) enabled evaluation of their immunogenicity. Lymphocyte proliferation responses did not indicate substantial diagnostic potential of the antigens tested. In contrast serum antibody levels for MAP1138c in paratuberculosis infected cows (N=20) were significantly higher (p<0.01) than in control animals (N=20), despite the conserved nature of this protein. In conclusion, this study showed that a combination of proteomics and genomics, starting from complex protein mixtures, present in tuberculins, can reveal novel proteins aiding the development of immunodiagnostics for mycobacterial diseases.
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Affiliation(s)
- Wiebren Santema
- Department of Infectious Diseases and Immunology, Immunology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
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Janowski R, Auerbach-Nevo T, Weiss MS. Bacterioferritin from Mycobacterium smegmatis contains zinc in its di-nuclear site. Protein Sci 2008; 17:1138-50. [PMID: 18445621 DOI: 10.1110/ps.034819.108] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Bacterioferritins, also known as cytochrome b (1), are oligomeric iron-storage proteins consisting of 24 identical amino acid chains, which form spherical particles consisting of 24 subunits and exhibiting 432 point-group symmetry. They contain one haem b molecule at the interface between two subunits and a di-nuclear metal binding center. The X-ray structure of bacterioferritin from Mycobacterium smegmatis (Ms-Bfr) was determined to a resolution of 2.7 A in the monoclinic space group C2. The asymmetric unit of the crystals contains 12 protein molecules: five dimers and two half-dimers located along the crystallographic twofold axis. Unexpectedly, the di-nuclear metal binding center contains zinc ions instead of the typically observed iron ions in other bacterioferritins.
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Antigenic profiles of recombinant proteins from Mycobacterium avium subsp. paratuberculosis in sheep with Johne's disease. Vet Immunol Immunopathol 2008; 122:116-25. [DOI: 10.1016/j.vetimm.2007.10.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 10/18/2007] [Accepted: 10/25/2007] [Indexed: 11/21/2022]
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7
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Eda S, Elliott B, Scott MC, Waters WR, Bannantine JP, Whitlock RH, Speer CA. New method of serological testing for Mycobacterium avium subsp. paratuberculosis (Johne's disease) by flow cytometry. Foodborne Pathog Dis 2005; 2:250-62. [PMID: 16156706 DOI: 10.1089/fpd.2005.2.250] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Johne's disease (JD) or paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is one of the most widespread and economically important diseases of livestock and wild ruminants worldwide. Attempts to control JD have proven inordinately difficult due to low levels of sensitivity by currently available diagnostic tests, which are also incapable of detecting prepatent MAP infections. In the present work, we describe the use of a flow cytometry method (FCM) for serological diagnosis of subclinical and clinical JD in cattle. The FCM was capable of distinguishing MAP-infected from MAP-non-infected cattle as well as MAP from M. scrofulaceum and M. avium subsp. avium. Results of the FCM were compared to that of a commercially available ELISA using 82 serum samples from JD-positive and JD-negative dairy and beef cattle farms that were separated into the following groups: (1) sera from a JD-free farm; (2) sera from JD-positive farms that had tested negative by ELISA; and (3) sera from JD-positive farms that tested JD-positive by ELISA. The FCM found that groups 1-3 were 6.6%, 73.3%, and 97.3% positive for MAP infections, respectively. By using 30 fecal culture-negative samples from a JD-free farm and 21 fecal culture-positive samples from JD-positive farms, diagnostic sensitivity and specificity of the FCM were calculated to be 95.2% and 96.7%, respectively. A retrospective study of 10 JD-positive cows showed that the FCM detected MAP infections 6-44 months earlier than the fecal culture test. Further, the FCM specifically detected MAP infections in serum samples as early as 170 days after experimental inoculation of calves with MAP and did not react with calves inoculated with other mycobacteria. Production of IgG against MAP was detected by FCM in all the calves inoculated with MAP 240 days after inoculation, whereas positive anti-MAP IgG production was not detected in control calves or calves experimentally infected with M. avium subsp. avium or M. bovis. The FCM assay is rapid and is completed in less than 4 h. Moreover, the FCM is objective, technically easy and can be automated for handling large numbers of samples. This novel assay might form the basis of a highly sensitive and subspecies-specific test for the diagnosis of JD.
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Affiliation(s)
- S Eda
- Center for Wildlife Health, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996, USA
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Abstract
Paratuberculosis is a chronic, granulomatous enteritis caused by Mycobacterium avium subspecies paratuberculosis affecting domestic and wild ruminants. The symptoms of clinical paratuberculosis are chronic diarrhoea and progressive weight loss while subclinically infected animals mainly have decreased production. The infection is widespread throughout the world and causes substantial financial losses for the farming industry. One of the major obstacles in the control of this disease, is the difficulty of identifying subclinically infected animals. This review gives a summary of several aspects of paratuberculosis including clinical importance, pathology, immunology and properties of the infectious agent. Special emphasis will be on the available diagnostic methods, their use and limitations.
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Affiliation(s)
- I Olsen
- National Veterinary Institute, Oslo, Norway.
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Rajukumar K, Tripathi BN, Kurade NP, Parihar NS. An enzyme-linked immunosorbent assay using immonoaffinity-purified antigen in the diagnosis of caprine paratuberculosis and its comparison with conventional ELISAs. Vet Res Commun 2001; 25:539-53. [PMID: 11583377 DOI: 10.1023/a:1017921115441] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
An enzyme-linked immunosorbent assay (APA-ELISA) using an immunoaffinity-purified antigen was developed and compared with the unabsorbed and absorbed ELISA procedures, using a crude antigenic preparation, for its efficacy in detecting antibodies in goat sera against Mycobacterium ovium paratuberculosis. Serum samples from 89 goats belonging to three different flocks, two with a history and evidence of paratuberculosis and one without it, were subjected to each ELISA, which had been standardized on known positive sera from goats experimentally infected with paratuberculosis. Faecal culture, faecal examination and histopathology were used as indicators of infection. The diagnostic sensitivities of the unabsorbed, absorbed and APA-ELISA were 81.8%, 77.3% and 77.3% and the specificities were 90.6%, 93.7% and 96.8%, respectively. The positive predictive values of APA-ELISA (94.4%) was the highest, followed by absorbed ELISA (80.9%) and unabsorbed ELISA (72.0%). The negative predictive values for APA-ELISA, absorbed ELISA and unabsorbed ELISA were 93.0%, 92.7% and 93.8%, respectively. The results indicated the value of APA-ELISA in avoiding the need to absorb individual test sera with Mycobacterium phlei and giving more consistent results than the absorbed ELISA. The APA-ELISA was also better than the other two procedures in terms of specificity and positive predictive values.
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Affiliation(s)
- K Rajukumar
- High Security Animal Disease Laboratory, Indian Veterinary Research Institute, RS, Anand Nagar, Bhopal
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Olsen I, Reitan LJ, Wiker HG. Distinct differences in repertoires of low-molecular-mass secreted antigens of Mycobacterium avium complex and Mycobacterium tuberculosis. J Clin Microbiol 2000; 38:4453-8. [PMID: 11101579 PMCID: PMC87620 DOI: 10.1128/jcm.38.12.4453-4458.2000] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Antigens in a 4-week-old culture filtrate (CF) of Mycobacterium avium subsp. avium were separated in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by Western blotting. The culture had minimal lysis of bacilli, giving a CF preparation consisting mainly of secreted proteins. Comparison with a similar CF of Mycobacterium tuberculosis with almost no contamination with intracellular proteins showed the presence of cross-reactive antigens homologous to the four components of the antigen 85 complex, as well as MPT32. These were major constituents of the M. avium subsp. avium CF. In addition, there were several low-molecular-mass bands (<15 kDa) in both species that did not cross-react with polyclonal and polyvalent rabbit antibodies in Western blotting. Furthermore, these bands were not detected in corresponding sonicate preparations, indicating high localization indexes, which is typical of soluble secreted proteins. A 14-kDa protein was selected for purification and more detailed characterization. The N-terminal amino acid sequence was determined, and a matching gene was found within the genomic sequence of M. avium subsp. avium which was highly homologous to Rv0455c of M. tuberculosis. The gene encoded a signal peptide typical of secreted mycobacterial proteins. A rabbit antiserum was raised against the purified protein, and the antigen was demonstrated by Western blotting in CFs of M. avium subsp. avium, Mycobacterium avium subsp. paratuberculosis, Mycobacterium intracellulare, and Mycobacterium scrofulaceum but was not detected in M. tuberculosis. This is a new example of a highly homologous gene being differentially expressed by different mycobacterial species.
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Affiliation(s)
- I Olsen
- National Veterinary Institute, Institute of Immunology (IGRI), Oslo, Norway.
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Olsen I, Reitan LJ, Holstad G, Wiker HG. Alkyl hydroperoxide reductases C and D are major antigens constitutively expressed by Mycobacterium avium subsp. paratuberculosis. Infect Immun 2000; 68:801-8. [PMID: 10639449 PMCID: PMC97208 DOI: 10.1128/iai.68.2.801-808.2000] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Antigens characteristic for Mycobacterium avium subspecies paratuberculosis were identified by crossed immunoelectrophoresis (CIE) and by absorbing out cross-reactive antigens by using a polyclonal and polyvalent Mycobacterium avium subspecies avium antiserum. Two antigens were present in M. avium subsp. paratuberculosis and not detected in Mycobacterium avium subsp. avium. They were identified as antigens 17 and 20 in a CIE reference system for M. avium subsp. paratuberculosis antigens. Purified antigen 20 was identified as alkyl hydroperoxide reductase C (AhpC) while the N-terminal part of purified antigen 17 showed 80% homology with alkyl hydroperoxide reductase D (AhpD) of Mycobacterium tuberculosis. AhpC had a nonreduced mobility in sodium dodecyl sulfate-polyacrylamide gel electrophoresis corresponding to a molecular mass of 45 kDa and is probably a homodimer linked with disulfide bridges in its native form. AhpD had a mobility corresponding to 19 kDa. Monospecific rabbit antiserum against AhpC and AhpD reacted with 9 strains of M. avium subsp. paratuberculosis but not with 20 other mycobacterial strains except for a Mycobacterium gordonae strain, against which a weak cross-reactive band was produced. Goats experimentally infected with M. avium subsp. paratuberculosis had strong gamma interferon (IFN-gamma) responses toward both AhpC and AhpD, and they also had antibodies against AhpC. The ability of AhpC and AhpD to induce IFN-gamma production shows that these proteins potentially could be used in future vaccines or in diagnostic assays. These results further show that AhpC and AhpD are immunologically important proteins which are constitutively and highly expressed in M. avium subsp. paratuberculosis without the bacteria being submitted to oxidative stress and that the specificities of antigens can be a matter of different levels of protein expression in various species as well as distinct structural differences.
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Affiliation(s)
- I Olsen
- National Veterinary Institute, The National Hospital, Oslo, Norway.
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12
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Coetsier C, Havaux X, Mattelard F, Sadatte S, Cormont F, Buergelt K, Limbourg B, Latinne D, Bazin H, Denef JF, Cocito C. Detection of Mycobacterium avium subsp. paratuberculosis in infected tissues by new species-specific immunohistological procedures. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 1998; 5:446-51. [PMID: 9665946 PMCID: PMC95597 DOI: 10.1128/cdli.5.4.446-451.1998] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We have previously described the cloning and sequencing of a gene portion coding for the terminal part of a 34-kDa protein of Mycobacterium avium subsp. paratuberculosis, the etiological agent of Johne's disease (P. Gilot, M. De Kesel, L. Machtelinckx, M. Coene, and C. Cocito, J. Bacteriol. 175:4930-4935, 1993). The recombinant polypeptide (a362) carries species-specific B-cell epitopes which do not cross-react with other mycobacterial pathogens (M. De Kesel, P. Gilot, M.-C. Misonne, M. Coene, and C. Cocito, J. Clin. Microbiol. 31:947-954, 1993). The present work describes the preparation of polyclonal and monoclonal antibodies directed against a362 and the use of these immunoglobulins for histopathological diagnosis of Johne's disease. The new immunohistological procedures herewith detailed proved to be able to identify M. avium subsp. paratuberculosis antigens in the intestinal tissues and lymph nodes of cattle affected by either the paucibacillary or pluribacillary form of the disease. They yielded negative responses not only with healthy animals but also with those affected by tuberculosis (Mycobacterium bovis). Both immunohistological procedures proved to be as sensitive as or more sensitive than Ziehl-Neelsen staining and, in addition, to be endowed with species specificity.
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Affiliation(s)
- C Coetsier
- Histology Unit, University of Louvain Medical School, Brussels, Belgium
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El-Zaatari FA, Naser SA, Graham DY. Characterization of a specific Mycobacterium paratuberculosis recombinant clone expressing 35,000-molecular-weight antigen and reactivity with sera from animals with clinical and subclinical Johne's disease. J Clin Microbiol 1997; 35:1794-9. [PMID: 9196196 PMCID: PMC229844 DOI: 10.1128/jcm.35.7.1794-1799.1997] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Johne's disease is a chronic enteritis of ruminants associated with enormous worldwide economic losses for the dairy cow- and goat-rearing industries. Management limitations and eradication programs for this disease have been hampered by the lack of a simple and specific diagnostic test for the detection of subclinical cases. We used a recombinant clone expressing a 35,000-molecular-weight Mycobacterium paratuberculosis antigen (p35 antigen) from a previously constructed expression library of M. paratuberculosis in Escherichia coli. The DNA fragment encoding the p35 gene hybridized only to DNA from Mycobacterium avium complex, but not to DNAs from other mycobacteria and nonmycobacterial organisms. The seroreactivity of p35 was evaluated by immunoblotting against 57 reference serum samples obtained from infected and uninfected animals. p35 was recognized by sera from 100% of animals with advanced Johne's disease (clinical stage) (12 cattle, 2 goats, and 2 sheep) and by sera from 75% of 20 cattle with early infection (subclinical stage). None of the sera from 15 M. paratuberculosis-free cows, 3 Mycobacterium bovis BCG-infected tuberculous cattle, or 3 cows artificially inoculated with multiple doses of viable M. paratuberculosis reacted with p35. The overall sensitivity, specificity, positive predictive value, and negative predictive value were 86, 100, 100, and 75%, respectively. The accuracy of p35 immunoblotting was superior to those of commercially available diagnostic tests for Johne's disease. These results suggest that the p35 recombinant protein has potential for use in the serodiagnosis of animals with Johne's disease at all stages of infection. The DNA fragment encoding p35 may also serve as a probe for identification of M. avium complex infection.
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Affiliation(s)
- F A El-Zaatari
- Inflammatory Bowel Disease Laboratory, Veterans Affairs Medical Center, Baylor College of Medicine, Houston, Texas 77030, USA.
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Stevenson K, Sharp JM. The contribution of molecular biology to Mycobacterium avium subspecies Paratuberculosis research. Vet J 1997; 153:269-86. [PMID: 9232117 DOI: 10.1016/s1090-0233(97)80062-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Molecular biology has contributed to our knowledge and understanding of the structure of Mycobacterium avium subspecies paratuberculosis and has been particularly useful in determining those components that elicit immune responses in the host or discriminate M. avium paratuberculosis from other closely related environmental mycobacteria. As such, it has made a significant impact in the field of diagnosis, and has been instrumental in the development of specific and sensitive diagnostic tests. The next decade will see exciting new developments in paratuberculosis research as a consequence of substantial advances made in the construction of gene transfer systems in mycobacteria. These will provide opportunities for applying new strategies to determine the genetic basis for pathogenesis and the mechanisms of drug resistance and will offer new prospects for the rational design of efficient vaccines.
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Affiliation(s)
- K Stevenson
- Moredun Research Institute, Edinburgh, Scotland, UK
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Mutharia LM, Moreno W, Raymond M. Analysis of culture filtrate and cell wall-associated antigens of Mycobacterium paratuberculosis with monoclonal antibodies. Infect Immun 1997; 65:387-94. [PMID: 9009287 PMCID: PMC174607 DOI: 10.1128/iai.65.2.387-394.1997] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Proteins secreted by Mycobacterium species have been suggested as major immune targets in the early phase of infection. In this study, we sought to identify specific antigens in culture filtrates and in soluble cell extracts of Mycobacterium paratuberculosis. The release of antigens into the culture medium during growth of the bacilli and the distribution of specific epitopes within the Mycobacterium species were investigated by immunoblot analysis with monoclonal antibodies (MAbs) raised against M. paratuberculosis antigens. MAb B6A interacted with a cellular antigen with an apparent molecular mass of 34.5 kDa in lysates of M. paratuberculosis. MAb B6A did not interact with lysates from any other mycobacterial species, suggesting recognition of an M. paratuberculosis species-specific epitope. MAb FL1-A1 reacted with an antigen of 44.3 kDa in M. paratuberculosis and a 9-kDa antigen in Mycobacterium kansasii. MAb PII-B1 reacted with concanavalin A (ConA)-binding cellular and filtrate molecules of M. paratuberculosis and with lysates of Mycobacterium kansasii and Mycobacterium avium 18. The affinity-purified glycosylated antigens migrated as a diffuse band of between 35 and 45.6 kDa and reacted strongly with ovine and bovine paratuberculosis serum and polyclonal serum against M. tuberculosis lipoarabinomannan antigens. These glycoconjugates were the earliest antigens detected in culture filtrates of M. paratuberculosis. Deglycosylation of the ConA-binding molecules with alpha-mannosidase enzyme abolished the reaction with MAb PII-B1 and with bovine but not ovine paratuberculosis serum, suggesting selective immunogenicity in the different animal species.
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Affiliation(s)
- L M Mutharia
- Department of Microbiology, University of Guelph, Ontario, Canada.
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Sugden EA, Stilwell K, Watson DC, Rohonczy EB, Martineau P. Purification of Mycobacterium bovis BCG Tokyo antigens by chromatofocusing, lectin-affinity chromatography, and hydrophobic interaction chromatography. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 1996; 3:541-6. [PMID: 8877132 PMCID: PMC170403 DOI: 10.1128/cdli.3.5.541-546.1996] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A combination of chromatofocusing, lectin-affinity chromatography, and hydrophobic interaction chromatography resulted in a simple purification of protein antigens of Mycobacterium bovis BCG Tokyo culture filtrate. Identification was established on the basis of chromatographic separation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis determination of molecular weights, and N-terminal amino acid determination. Chromatofocusing on PBE 94 accomplished the separation of BCG85B from other BCG85 complex antigens and partial separation of MPB64 and MPB70 antigens. Subsequently, MPB64 and MPB70 were completely separated on a high-performance liquid chromatography TSK Phenyl 5PW hydrophobic interaction chromatography column. This column also separated BCG85B from a 17-kDa protein with an N-terminal amino acid sequence of A-V-P-I-T-G-K-L-G-S-E-L-T-M-T-D-( )-V-G-Q, which is similar to the sequence of MPT63. Concanavalin A-Sepharose-affinity chromatography separated MPB64 from a 43- and 47-kDa doublet with an amino acid sequence of D-P-E-P-A-P-P-V-P-P-V-P-A-( )-A-A-S-P, which is similar to the sequence of MPT32 and which appears to be glycosylated.
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Affiliation(s)
- E A Sugden
- Agriculture and Agri-Food Canada, Animal Diseases Research Institute, Nepean, Ontario, Canada.
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Stehman SM. Paratuberculosis in small ruminants, deer, and South American camelids. Vet Clin North Am Food Anim Pract 1996; 12:441-55. [PMID: 8828115 DOI: 10.1016/s0749-0720(15)30416-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Paratuberculosis in small ruminants is widespread geographically. In some herds and flocks, clinical paratuberculosis, which primarily causes long-term weight loss, can be a significant cause of culling. The effects of subclinical disease are less defined, but they may include decreased milk production in milking sheep and decreased weight gain in deer raised for slaughter. Paratuberculosis also can cause economic losses due to reduced sales of breeding animals from purebred flocks and herds. Diagnosis in goats, deer, and SACs is based primarily on feces or tissue culture and histopathologic examination. Because of the difficulty in growing sheep strains of M. paratuberculosis, diagnosis is based on finding compatible histopathologic lesions with acid-fast organisms. The AGID is a highly specific serologic test for diagnosis of clinical paratuberculosis that correlates with fecal shedding of organisms and degree of severity of lesions; however, it is less sensitive than fecal culture at the herd level for detection of subclinical disease. The CF test detects clinically affected animals but yields poor specificity. The ELISA test is being evaluated for use as a herd screening test in sheep, goats, and SACs. The test seems to be as sensitive as the AGID test but shows a lack of specificity in herds and flocks infected with caseous lymphadenitis. Absorption of sera with Corynebacterium pseudotuberculosis or Mycobacterium phlei may improve specificity, but more studies are needed. Currently, the ELISA test is best used only as a herd or flock screening tool; its use for diagnosis of individual cases requires confirmation with a more specific serologic test or organism detection test such as fecal culture or PCR. Paratuberculosis can be managed and eliminated by combining stringent management with frequent testing and culling or by combining vaccination (where permitted) with management of fecal-oral transmission. Management of fecal-oral transmission is particularly important to prevent exposure of young stock to the infection. Control programs differ with the goals and economics of each farm. The frequency of testing and level of management intervention are determined by each farm's abilities, priorities, and finances.
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Affiliation(s)
- S M Stehman
- Diagnostic Laboratory, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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Dubash K, Shulaw WP, Bech-Nielsen S, Stills HF, Slemons RD. Evaluation of an enzyme-linked immunosorbent assay licensed by the USDA for use in cattle for diagnosis of ovine paratuberculosis. J Vet Diagn Invest 1995; 7:347-51. [PMID: 7578450 DOI: 10.1177/104063879500700309] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A commercially available Mycobacterium phlei-absorbed enzyme-linked immunosorbent assay (ELISA) approved to detect antibodies to Mycobacterium paratuberculosis in cattle was evaluated for its applicability in sheep. The potential for interference with ELISA results from cross-reacting antibodies to Corynebacterium pseudotuberculosis was also investigated. Serum samples were randomly selected from a collection of samples obtained in 1986-1991 from 6 infected and 5 noninfected sheep flocks varying in breed, age, and geographic origin. Tests were performed on sera from 27 paratuberculous sheep, confirmed by histopathology, bacteriologic culture, and/or acid-fast staining of ileal mucosal smears, and on sera from 246 noninfected sheep. The optical density of each sample was expressed as a percentage of the optical density of a known positive sheep serum sample tested on the same plate. These values were log-transformed to achieve normality of distribution, and sensitivity and specificity estimates were calculated based on 2 and 3 standard deviations above the mean of the percent positive value (PPV) of the noninfected sheep. A cutoff value of PPV > or = 55.74 resulted in an estimated sensitivity of 0.48 and a specificity of 0.95. Sera from 10 noninfected sheep with PPV above the cutoff level of 55.74% were absorbed with heat-treated C. pseudotuberculosis organisms in addition to M. phlei antigens. Sera from 14 ELISA-positive paratuberculous sheep and 23 ELISA-negative noninfected sheep were similarly treated, and results were compared. Absorption with C. pseudotuberculosis resulted in a significant decrease in PPV in all 3 groups of sheep sera, but a greater decrease was observed in the noninfected sheep with PPV above the cutoff level when compared with noninfected sheep with PPV below that level. Results of this study suggest that ELISA may be of value in screening sheep flocks for paratuberculosis, but further experimentation is needed to optimize the sensitivity and specificity of the assay. Exposure to C. pseudotuberculosis may confound results obtained by M. phlei-absorbed ELISA for paratuberculosis.
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Affiliation(s)
- K Dubash
- Department of Veterinary Preventive Medicine, Ohio State University, Columbus 43210, USA
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19
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Deshpande RG, Khan MB, Bhat DA, Navalkar RG. Immunoaffinity chromatographic isolation of a high molecular weight seroreactive protein from Mycobacterium leprae cell sonicate. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1995; 11:163-9. [PMID: 7581267 DOI: 10.1111/j.1574-695x.1995.tb00113.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The purpose of this study was to isolate Mycobacterium leprae antigen(s) by immunoaffinity chromatography using immunoglobulins from leprosy patients and from rabbit anti-M. leprae hyperimmune serum coupled to CNBr-Sepharose 4B. A high molecular weight (M(r)) M. leprae protein (MLP) with a subunit M(r) of 22,000 was isolated. MLP was recognized by monoclonal antibody MMPII1G4 which is known to react with MMPII, a 22 kDa protein of M. leprae. The N-terminal sequence of the 22 kDa subunit (Met-gln-gly-asp-pro-asp-val-leu-arg-leu-leu-asn-glu-gln-leu-thr) was identical to MMPII and to antigen D (bacterioferritin) of M. paratuberculosis. It showed 44% homology with N-terminal end of E. coli bacterioferritin. In ELISA, MLP showed 100% and 60% positivity with leprosy and TB sera respectively as compared to normal healthy sera. The role of bacterioferritin in M. leprae and the importance of MLP as an immunogen has been discussed.
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Affiliation(s)
- R G Deshpande
- Department of Microbiology and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA
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20
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Burrells C, Inglis NF, Davies RC, Sharp JM. Detection of specific T cell reactivity in sheep infected with Mycobacterium avium subspecies silvaticum and paratuberculosis using two defined mycobacterial antigens. Vet Immunol Immunopathol 1995; 45:311-20. [PMID: 7545852 DOI: 10.1016/0165-2427(94)05347-u] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A 30 kDa antigen (P30) from Mycobacterium avium ssp. paratuberculosis (M. a. paratuberculosis) and a 40 kDa (P40) antigen from Mycobacterium avium ssp. silvaticum (M. a. silvaticum) were employed in two different assays to measure the cell-mediated immune reactivity of ovine peripheral blood lymphocytes. In lymphocyte stimulation assays, proliferative responses to the P30 were observed only with lymphocytes from sheep inoculated with live M. a. paratuberculosis or M. a. silvaticum. Although this antigen was not subspecies-specific it differentiated between animals given live organisms and those inoculated with an inactive lysate. The P40 protein from M. a. silvaticum showed subspecies specificity by eliciting in vitro responses only with lymphocytes derived from sheep inoculated with live M. a. silvaticum. Similar results were obtained using an interferon-gamma release assay which proved to be a more rapid and sensitive system.
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Affiliation(s)
- C Burrells
- Moredun Research Institute, Edinburgh, UK
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21
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Pessolani MC, Smith DR, Rivoire B, McCormick J, Hefta SA, Cole ST, Brennan PJ. Purification, characterization, gene sequence, and significance of a bacterioferritin from Mycobacterium leprae. J Exp Med 1994; 180:319-27. [PMID: 8006590 PMCID: PMC2191570 DOI: 10.1084/jem.180.1.319] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The study of tissue-derived Mycobacterium leprae provides insights to the immunopathology of leprosy and helps identify broad molecular features necessary for mycobacterial parasitism. A major membrane protein (MMP-II) of in vivo-derived M. leprae previously recognized (Hunter, S.W., B. Rivoire, V. Mehra, B.R. Bloom, and P.J. Brennan. 1990. J. Biol. Chem. 265:14065) was purified from extracts of the organism and partial amino acid sequence obtained. This information allowed recognition, within one of the cosmids that encompass the entire M. leprae genome, of a complete gene, bfr, encoding a protein of subunit size 18.2 kD. The amino acid sequence deduced from the major membrane protein II (MMP-II) gene revealed considerable homology to several bacterioferritins. Analysis of the native protein demonstrated the iron content, absorption spectrum, and large native molecular mass (380 kD) of several known bacterioferritins. The ferroxidase-center residues typical of ferritins were conserved in the M. leprae product. Oligonucleotides derived from the amino acid sequence of M. leprae bacterioferritin enabled amplification of much of the MMP-II gene and the detection of homologous sequences in Mycobacterium paratuberculosis, Mycobacterium avium, Mycobacterium tuberculosis, Mycobacterium intracellulare, and Mycobacterium scrofulaceum. The role of this iron-rich protein in the virulence of M. leprae is discussed.
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Affiliation(s)
- M C Pessolani
- Department of Microbiology, Colorado State University, Fort Collins 80523
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Abstract
Paratuberculosis (Johne's disease) is a chronic, wasting, widespread mycobacteriosis of ruminants. It involves extensive mycobacterial shedding, which accounts for the high contagiousness, and ends with a fatal enteritis. Decreases in weight, milk production, and fertility produce severe economic loss. The DNA of the etiological agent (Mycobacterium paratuberculosis) has a base composition (66 to 67% G+C) within the range of that of mycobacteria (62 to 70% G+C), a size (4.4 x 10(6) to 4.7 x 10(6) bp) larger than that of most pathogenic mycobacteria (2.0 x 10(6) to 4.2 x 10(6) bp), and a high relatedness (> 90%) to Mycobacterium avium DNA. However, the DNAs of the two organisms can be distinguished by restriction fragment length polymorphism analysis. M. paratuberculosis genes coding for a transposase, a cell wall-associated protein (P34), and two heat shock proteins have been cloned and sequenced. Nucleic acid probes (two of which are species specific) are used, after PCR amplification, for M. paratuberculosis identification in stools and milk. As in leprosy, with disease progression, cellular immune reactions decrease and humoral immune reactions increase. Cutaneous testing with sensitins, lymphocyte proliferation assays, and cytokine tests are used to monitor cellular immune reactions in paratuberculosis, but these tests lack specificity. Complement fixation, immunodiffusion, and enzymometric tests based on antibodies to M. paratuberculosis extracts, to mycobacterial antigen complex A36, to glycolipids, and to proteins help identify affected cattle but are not species specific. The carboxyl-terminal portion of the 34-kDa cell wall-associated A36 protein (P34) carries species-specific B-cell epitopes and is the basis for an enzyme-linked immunosorbent assay. Diagnostic tests for paratuberculosis are also used in Crohn's disease, a chronic human ileitis mimicking Johne's disease, in which isolates identified as M. paratuberculosis have been found.
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Affiliation(s)
- C Cocito
- Microbiology and Genetics Unit, University of Louvain, Medical School, Brussels, Belgium
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De Kesel M, Gilot P, Misonne MC, Coene M, Cocito C. Cloning and expression of portions of the 34-kilodalton-protein gene of Mycobacterium paratuberculosis: its application to serological analysis of Johne's disease. J Clin Microbiol 1993; 31:947-54. [PMID: 7681851 PMCID: PMC263592 DOI: 10.1128/jcm.31.4.947-954.1993] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Paratuberculosis (Johne's disease), an endemic mycobacteriosis of cattle that is caused by Mycobacterium paratuberculosis, is characterized by incoercible diarrhea and fecal shedding of bacteria. The present work aimed at developing a specific serological test for this disease. We have recently shown that a 34-kDa protein belonging to the major antigen complex A36 of M. paratuberculosis is immunodominant and contains epitopes specific with respect to all mycobacteria tested, including Mycobacterium bovis and the closely related species Mycobacterium avium. From a lambda gt11 genomic library of M. paratuberculosis, three portions of the gene coding for this 34-kDa protein have been isolated. Two of them expressed cross-reacting mycobacterial epitopes. One portion (in clone a362) expressed a polypeptide which cross-reacted with all tested M. paratuberculosis strains but not with 20 other bacteria tested, including many strains of the M. avium-Mycobacterium intracellulare-Mycobacterium scrofulaceum group. The occurrence at the M. paratuberculosis surface of epitopes corresponding to the a362 polypeptide was shown by immune electron microscopy. The recombinant a362 polypeptide was used as reagent for an enzyme-linked immunoassay for paratuberculosis. This assay correctly diagnosed all the tested blood samples from infected cattle at all stages of the disease.
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Affiliation(s)
- M De Kesel
- Microbiology and Genetics Unit, Medical School, University of Louvain, Brussels, Belgium
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Elsaghier A, Prantera C, Moreno C, Ivanyi J. Antibodies to Mycobacterium paratuberculosis-specific protein antigens in Crohn's disease. Clin Exp Immunol 1992; 90:503-8. [PMID: 1281056 PMCID: PMC1554584 DOI: 10.1111/j.1365-2249.1992.tb05874.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The possible role of infection with Mycobacterium paratuberculosis (MAP) for the etiopathogenesis of Crohn's disease (CD) has been a matter of long-term controversy. In addition to similarities with the pathology of ruminant paratuberculosis, DNA fingerprinting confirmed the organism isolated from gut tissue, but the specificity of the immune repertoire has not as yet been evaluated. We report here on a serological study of 29 patients with CD, 20 patients with ulcerative colitis and 18 healthy control subjects, using three antigens attributed with species-specificity and selective immunogenicity following MAP infection. Antibodies binding to the 38-kD band of MAP extract were demonstrable by the Western blot technique in 57% of CD patients. Antibody levels to the 24-kD (p24BCD) cathodic bands, determined by competition ELISA using a monospecific murine antiserum, and to the 18-kD protease-resistant purified bacterioferritin, detected by standard ELISA, were significantly elevated in 53% of CD patients. However, these three antibody specificities tested in individual CD patients did not show any correlation with each other. Thus, 18% of patients were positive for all three specificities, whilst 84% had antibodies to at least one of the specific antigens. Although the exact proportion of affected patients is yet to be defined, the serological results obtained support the view that MAP infection may play an etiological role in Crohn's disease.
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Affiliation(s)
- A Elsaghier
- Tuberculosis and Related Infections Unit, Royal Postgraduate Medical School, London, UK
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Elsaghier A, Nolan A, Allen B, Ivanyi J. Distinctive western blot antibody patterns induced by infection of mice with individual strains of the Mycobacterium avium complex. Immunol Suppl 1992; 76:355-61. [PMID: 1526646 PMCID: PMC1421692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Systemic infection of mice with organisms of the Mycobacterium avium complex (MAC) induced antibody responses, characteristic for each of the three tested individual strains. The influence of host genetic factors was reflected up to 3 months after infection by the finding of generally oligobanded and multibanded Western blot patterns in C57B1/6 and BALB/c mice, respectively. Nevertheless, more bands developed at 6 months in C57BL/6 mice. The response to three antigens of 18,000, 38,000 and 24,000 MW was analysed in greater detail. Antibodies to a protease-resistant 18,000 MW band produced only by BALB/c mice were either strain specific, following infection with M. avium, strain Maa-B2, or cross-reactive within MAC, following infection with M. avium strain Maa-A6 and M. paratuberculosis, strain Map-203. Another protease-resistant antigen of 38,000 MW was immunogenic only in Maa-B2 infected mice. This constituent was found to be related to the protease-sensitive antigen of corresponding molecular weight from M. tuberculosis. Two 24,000 MW proteins of M. paratuberculosis were separated by two-dimensional gel electrophoresis: antibodies to the anodic band were induced by Map-203 infection, whilst the cathodic band was revealed by heteroclitic antibodies from Maa-B2-infected mice. The latter antigen is apparently expressed during in vivo replication, but not during in vitro culture of Maa-B2 bacteria. We generally conclude, that the selective antibody patterns after live infection, could be attributed to differences in the release of native antigens within mycobacterial lesions. In view of a high degree of species specificity, some of the immunogenic constituents identified may also be useful for serodiagnostic application.
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Affiliation(s)
- A Elsaghier
- MRC Tuberculosis and Related Infections Unit, Royal Postgraduate Medical School, London, U.K
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Brooks BW, Young NM, Watson DC, Robertson RH, Sugden EA, Nielsen KH, Becker SA. Mycobacterium paratuberculosis antigen D: characterization and evidence that it is a bacterioferritin. J Clin Microbiol 1991; 29:1652-8. [PMID: 1761687 PMCID: PMC270179 DOI: 10.1128/jcm.29.8.1652-1658.1991] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
By using a combination of agarose and polyacrylamide gel electrophoresis, Mycobacterium paratuberculosis antigen D was resolved from a crude sonicated preparation of the organism and characterized as a component with a molecular mass of approximately 400,000 Da. While this component was composed mainly of protein, with unusually high proportions of glutamic acid and leucine, it was resistant to digestion with a number of proteolytic enzymes. Structural detail revealed by electron microscopy, amino acid sequence data, and the demonstration of a Soret band in its absorption spectrum indicated that antigen D was similar to an Escherichia coli bacterioferritin.
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Affiliation(s)
- B W Brooks
- Agriculture Canada, Animal Diseases Research Institute, Nepean, Ontario, Canada
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