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Chandra H, Gupta MK, Lam YW, Yadav JS. Predominantly Orphan Secretome in the Lung Pathogen Mycobacterium abscessus Revealed by a Multipronged Growth-Phase-Driven Strategy. Microorganisms 2024; 12:378. [PMID: 38399782 PMCID: PMC10892769 DOI: 10.3390/microorganisms12020378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
The emerging lung pathogen Mycobacterium abscessus is understudied for its virulence determinants and molecular targets for diagnosis and therapeutics. Here, we report a comprehensive secretome (600 proteins) of this species, which was identified using a multipronged strategy based on genetic/genomic, proteomic, and bioinformatic approaches. In-solution digested bottom-up proteomics from various growth phases identified a total of 517 proteins, while 2D-GE proteomics identified 33 proteins. A reporter-gene-fusion-based genomic library that was custom-generated in this study enabled the detection of 23 secretory proteins. A genome-wide survey for N-terminal signal sequences using bioinformatic tools (Psortb 2.0 and SignalP 3.0) combined with a strategy of the subtraction of lipoproteins and proteins containing multiple transmembrane domains yielded 116 secretory proteins. A homology search against the M. tuberculosis database identified nine additional secretory protein homologs that lacked a secretory signal sequence. Considering the little overlap (80 proteins) among the different approaches used, this study emphasized the importance of using a multipronged strategy for a comprehensive understanding of the secretome. Notably, the majority of the secreted proteins identified (over 50%) turned out to be "orphans" (those with no known functional homologs). The revelation of these species-specific orphan proteins offers a hitherto unexplored repertoire of potential targets for diagnostic, therapeutic, and vaccine research in this emerging lung pathogen.
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Affiliation(s)
- Harish Chandra
- Pulmonary/Microbial Pathogenesis Laboratory, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (H.C.)
| | - Manish K. Gupta
- Pulmonary/Microbial Pathogenesis Laboratory, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (H.C.)
| | - Ying-Wai Lam
- Vermont Biomedical Research Network Proteomics Facility, University of Vermont, Burlington, VT 05405, USA
| | - Jagjit S. Yadav
- Pulmonary/Microbial Pathogenesis Laboratory, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (H.C.)
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Prasad TSK, Verma R, Kumar S, Nirujogi RS, Sathe GJ, Madugundu AK, Sharma J, Puttamallesh VN, Ganjiwale A, Myneedu VP, Chatterjee A, Pandey A, Harsha H, Narayana J. Proteomic analysis of purified protein derivative of Mycobacterium tuberculosis. Clin Proteomics 2013; 10:8. [PMID: 23870090 PMCID: PMC3729367 DOI: 10.1186/1559-0275-10-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 07/16/2013] [Indexed: 12/02/2022] Open
Abstract
Background Purified protein derivative (PPD) has been used for more than half a century as an antigen for the diagnosis of tuberculosis infection based on delayed type hypersensitivity. Although designated as “purified,” in reality, the composition of PPD is highly complex and remains ill-defined. In this report, high resolution mass spectrometry was applied to understand the complexity of its constituent components. A comparative proteomic analysis of various PPD preparations and their functional characterization is likely to help in short-listing the relevant antigens required to prepare a less complex and more potent reagent for diagnostic purposes. Results Proteomic analysis of Connaught Tuberculin 68 (PPD-CT68), a tuberculin preparation generated from M. tuberculosis, was carried out in this study. PPD-CT68 is the protein component of a commercially available tuberculin preparation, Tubersol, which is used for tuberculin skin testing. Using a high resolution LTQ-Orbitrap Velos mass spectrometer, we identified 265 different proteins. The identified proteins were compared with those identified from PPD M. bovis, PPD M. avium and PPD-S2 from previous mass spectrometry-based studies. In all, 142 proteins were found to be shared between PPD-CT68 and PPD-S2 preparations. Out of the 354 proteins from M. tuberculosis–derived PPDs (i.e. proteins in either PPD-CT68 or PPD-S2), 37 proteins were found to be shared with M. avium PPD and 80 were shared with M. bovis PPD. Alignment of PPD-CT68 proteins with proteins encoded by 24 lung infecting bacteria revealed a number of similar proteins (206 bacterial proteins shared epitopes with 47 PPD-CT68 proteins), which could potentially be involved in causing cross-reactivity. The data have been deposited to the ProteomeXchange with identifier PXD000377. Conclusions Proteomic and bioinformatics analysis of different PPD preparations revealed commonly and differentially represented proteins. This information could help in delineating the relevant antigens represented in various PPDs, which could further lead to development of a lesser complex and better defined skin test antigen with a higher specificity and sensitivity.
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3
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Stavri H, Bucurenci N, Ulea I, Costache A, Popa L, Popa MI. Use of recombinant purified protein derivative (PPD) antigens as specific skin test for tuberculosis. Indian J Med Res 2012; 136:799-807. [PMID: 23287127 PMCID: PMC3573601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND & OBJECTIVES Purified protein derivative (PPD) is currently the only available skin test reagent used worldwide for the diagnosis of tuberculosis (TB). The aim of this study was to develop a Mycobacterium tuberculosis specific skin test reagent, without false positive results due to Bacillus Calmette-Guerin (BCG) vaccination using recombinant antigens. METHODS Proteins in PPD IC-65 were analyzed by tandem mass spectrometry and compared to proteins in M. tuberculosis culture filtrate; 54 proteins were found in common. Top candidates MPT64, ESAT 6, and CFP 10 were overexpressed in Escherichia coli expression strains and purified as recombinant proteins. To formulate optimal immunodiagnostic PPD cocktails, the antigens were evaluated by skin testing guinea pigs sensitized with M. tuberculosis H37Rv and BCG. RESULTS For single antigens and a cocktail mixture of these antigens, best results were obtained using 3 μg/0.1 ml, equivalent to 105 TU (tuberculin units). Each animal was simultaneously tested with PPD IC-65, 2 TU/0.1 ml, as reference. Reactivity of the multi-antigen cocktail was greater than that of any single antigen. The skin test results were between 34.3 and 76.6 per cent the level of reactivity compared to that of the reference when single antigens were tested and 124 per cent the level of reactivity compared to the reference for the multi-antigen cocktail. INTERPRETATION & CONCLUSIONS Our results showed that this specific cocktail could represent a potential candidate for a new skin diagnostic test for TB.
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Affiliation(s)
- Henriette Stavri
- Mycobacterial Antigens Laboratory & Enzymology & Applied Microbiology Laboratory, National Institute for Research & Development in Microbiology & Immunology, Cantacuzino, Romania,Reprint requests: Dr Henriette Stavri, Cantacuzino Institute, Mycobacterial Antigens Laboratory, Spl. Independentei 103, CP 1-525 050096, Bucharest, Romania e-mail:
| | - Nadia Bucurenci
- Mycobacterial Antigens Laboratory & Enzymology & Applied Microbiology Laboratory, National Institute for Research & Development in Microbiology & Immunology, Cantacuzino, Romania
| | - Irina Ulea
- Mycobacterial Antigens Laboratory & Enzymology & Applied Microbiology Laboratory, National Institute for Research & Development in Microbiology & Immunology, Cantacuzino, Romania
| | - Adriana Costache
- Mycobacterial Antigens Laboratory & Enzymology & Applied Microbiology Laboratory, National Institute for Research & Development in Microbiology & Immunology, Cantacuzino, Romania
| | - Loredana Popa
- University of Medicine & Pharmacy “Carol Davila”, Bucharest, Romania
| | - Mircea Ioan Popa
- University of Medicine & Pharmacy “Carol Davila”, Bucharest, Romania
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Yang H, Kruh-Garcia NA, Dobos KM. Purified protein derivatives of tuberculin--past, present, and future. ACTA ACUST UNITED AC 2012; 66:273-80. [PMID: 22762692 DOI: 10.1111/j.1574-695x.2012.01002.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 06/20/2012] [Accepted: 06/21/2012] [Indexed: 11/30/2022]
Abstract
The tuberculin skin test, which involves monitoring the immune reaction to an injection of purified protein derivative (PPD), has been the most widely used method for detecting infection with Mycobacterium tuberculosis since its development in 1930s. Until recently, the molecular composition of PPD was unknown. This thwarted the discovery of improved skin testing reagents and drastically hindered efforts to define the mechanism of action. Proteomic evaluation of PPD combined with a detailed analysis in the guinea pig model of tuberculosis led to further definition of the molecular composition of PPD. This communication reviews the history and current status of PPD, in addition to describing candidate next-generation PPD reagents, based on the use of an individual protein or protein cocktails.
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Affiliation(s)
- Hongliang Yang
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523-1682, USA
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Soldini S, Palucci I, Zumbo A, Sali M, Ria F, Manganelli R, Fadda G, Delogu G. PPE_MPTR genes are differentially expressed by Mycobacterium tuberculosis in vivo. Tuberculosis (Edinb) 2011; 91:563-8. [PMID: 21890414 DOI: 10.1016/j.tube.2011.08.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 07/14/2011] [Accepted: 08/08/2011] [Indexed: 10/17/2022]
Abstract
The PPE_MPTR protein sub-family is unique to mycobacteria and comprises proteins found only in MTB complex and in few other pathogenic mycobacteria. Very little is known about the precise function of PPE_MPTR, as well as on the expression pattern and the transcriptional regulation of their structural genes. In the present work, real time RT-PCR techniques were used to determine the expression profile of PPE_MPTR genes of Mycobacterium tuberculosis during infection in vivo and in different culture conditions. The PPE_MPTR genes showed a similar expression profile in axenic cultures, with a significant increase of gene expression following exposure to environmental signals such as SDS, isoniazid and ethambutol. The PPE_MPTR genes were expressed in lung and spleen tissues infected by M. tuberculosis, and levels of expression were similar to those of genes encoding M. tuberculosis virulence factors such as hbhA and mpt64. Levels and pattern of gene expression in host tissues were different for each PPE_MPTR gene under study. The results of this study indicate that PPE_MPTR genes are differentially regulated in the lung and spleen tissues during M. tuberculosis infection, suggesting that each gene responds independently to the different and complex environmental signals encountered in host tissues.
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Affiliation(s)
- Silvia Soldini
- Istituto di Microbiologia, Università Cattolica del Sacro Cuore, L.go A. Gemelli, 8, 00168 Rome, Italy
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Kozak R, Behr MA. Divergence of immunologic and protective responses of different BCG strains in a murine model. Vaccine 2010; 29:1519-26. [PMID: 21184855 DOI: 10.1016/j.vaccine.2010.12.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 12/01/2010] [Accepted: 12/02/2010] [Indexed: 01/24/2023]
Abstract
The ongoing evolution of BCG after its introduction in 1921 resulted in strains that differ genetically and phenotypically. Based on a genomic deletion (Region of Difference 2 or RD2) that occurred between 1927 and 1931, BCG strains can be sub-classified by the presence or absence of RD2. The existence of other mutations that distinguish BCG strains precludes simple comparison of RD2-positive and RD2-negative BCG strains to determine the importance, if any, of RD2 for vaccine protection. In this study, we have compared the RD2-containing BCG Russia, BCG Pasteur (which is a natural mutant for RD2), and BCG Pasteur complemented with RD2-genes Rv1979c-Rv1982 through various in vitro and in vivo assays of immunogenicity and protection. We determined that the presence of RD2 did not affect vaccine persistence, but lead to increased immunogenicity, as measured by ELISpot. Additionally, T-cells from animals immunized with BCG Russia and BCG Pasteur::Rv1979c-82 were more effective at killing Mycobacterium tuberculosis in macrophages than T-cells from animals immunized with BCG Pasteur. In a mouse vaccine-challenge model, the presence of RD2 had no effect on pulmonary TB, as measured by M. tuberculosis burden and degree of histopathology, at 4, 8 or 12 weeks post-infection. The presence of RD2 was however associated with decreased dissemination of M. tuberculosis to the spleen. Together, our data demonstrated that the loss of RD2 resulted in decreased immunogenicity but did not affect protection against pulmonary TB, indicating a dissociation between these phenotypes associated with BCG vaccination.
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Affiliation(s)
- R Kozak
- Department of Medicine, McGill University Health Centre, Montreal, QC, H3G 1A4 Canada
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Cloning of guinea pig IL-4: reduced IL-4 mRNA after vaccination or Mycobacterium tuberculosis infection. Tuberculosis (Edinb) 2010; 91:47-56. [PMID: 21167782 DOI: 10.1016/j.tube.2010.11.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 10/27/2010] [Accepted: 11/16/2010] [Indexed: 01/19/2023]
Abstract
Interleukin-4 (IL-4), a pleiotropic cytokine produced by T-helper type 2 (Th2) cells, is involved in promoting humoral immune responses, allergic reactions and asthma. Previous studies suggested an important role for IL-4 in susceptibility to pulmonary tuberculosis; however, the role of IL-4 has not been studied in the guinea pig, a highly relevant model for this disease. In the present study, we cloned a cDNA for guinea pig IL-4 and examined, for the first time, mRNA expression by real-time RT-PCR in cultured guinea pig cells. High levels of IL-4 mRNA expression were detected in spleen T cells of naïve animals after in vitro stimulation with PMA plus ionomycin for 4-24 h. The expression of IL-4 mRNA was low in spleen and lymph node cells immunized with ovalbumin (OVA) plus Complete Freund's Adjuvant (CFA) in response to OVA (Th1), but significantly higher in the guinea pigs immunized with OVA plus alum (Th2). BCG vaccination reduced the expression of IL-4 mRNA in both spleen and lung digest cells compared to naïve guinea pigs, while levels of IFN-γ were similar in both groups. Furthermore, lung cells from Mycobacterium tuberculosis-infected guinea pigs stimulated in vitro with PPD or MPT64 showed low levels of IL-4 mRNA expression. Thus, BCG vaccination or M. tuberculosis infection modulates IL-4 mRNA expression in the guinea pig. Cloning of guinea pig IL-4 will allow us to address the role of IL-4 in vaccine-induced resistance to pulmonary TB in a highly relevant animal model.
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Three protein cocktails mediate delayed-type hypersensitivity responses indistinguishable from that elicited by purified protein derivative in the guinea pig model of Mycobacterium tuberculosis infection. Infect Immun 2010; 79:716-23. [PMID: 21134965 DOI: 10.1128/iai.00486-10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Purified protein derivative (PPD) is a widely used reagent for the diagnosis of Mycobacterium tuberculosis infection. Recently, the molecular composition of PPD was defined, with hundreds of mycobacterial protein representatives making up PPD. Which, if any, of these specific products drive the potency of PPD remains in question. In this study, two proteins (DnaK and GroEL2) previously identified as dominant proteins in PPD were tested for the capacity to induce delayed-type hypersensitivity (DTH) responses in H37Rv-infected or BCG-vaccinated guinea pigs. These two proteins were used in pull-down assays to identify interacting PPD products. Six proteins were identified as interacting partners with DnaK and GroEL2, i.e., Rv0009, Rv0475, Rv0569, Rv0685, Rv2626c, and Rv2632c. These six proteins were tested alone and in combination with DnaK and GroEL2 for the capacity to induce a DTH response in the guinea pig model. From these studies, two cocktails, DnaK/GroEL2/Rv0009 and DnaK/GroEL2/Rv0685, were found to induce DTH responses in H37Rv-infected or BCG-vaccinated guinea pigs that were indistinguishable from DTH responses driven by a PPD injection. The mechanism by which DTH responses were induced was elucidated by histologic examination, analysis of activated CD4(+)/CD8(+) T cells, and cytokine mRNA expression at the site of the DTH response. PPD and the protein cocktails tested induced strong DTH responses in H37Rv-infected guinea pigs. Ex vivo phenotyping of T cells at the DTH site indicated that this response is mediated by activated CD4(+) and CD8(+) T cells, with increases in gamma interferon and tumor necrosis factor alpha, but not interleukin-10, at the site of the DTH response. Our results demonstrate for the first time that the PPD response can be mimicked at the molecular level with defined protein cocktails. The use of this defined product will allow a more thorough understanding of the DTH response and may provide a platform for more rapid and sensitive second-generation skin test reagents for the diagnosis of M. tuberculosis infection.
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Nicolò C, Sali M, Di Sante G, Geloso MC, Signori E, Penitente R, Uniyal S, Rinaldi M, Ingrosso L, Fazio VM, Chan BMC, Delogu G, Ria F. Mycobacterium smegmatisExpressing a Chimeric Protein MPT64-Proteolipid Protein (PLP) 139–151 Reorganizes the PLP-Specific T Cell Repertoire Favoring a CD8-Mediated Response and Induces a Relapsing Experimental Autoimmune Encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2009; 184:222-35. [DOI: 10.4049/jimmunol.0804263] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Wang Z, Potter BM, Gray AM, Sacksteder KA, Geisbrecht BV, Laity JH. The Solution Structure of Antigen MPT64 from Mycobacterium tuberculosis Defines a New Family of Beta-Grasp Proteins. J Mol Biol 2007; 366:375-81. [PMID: 17174329 DOI: 10.1016/j.jmb.2006.11.039] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 11/08/2006] [Accepted: 11/09/2006] [Indexed: 10/23/2022]
Abstract
The MPT64 protein and its homologs form a highly conserved family of secreted proteins with unknown function that are found within the pathogenic Mycobacteria genus. The founding member of this family from Mycobacterium tuberculosis (MPT64 or protein Rv1980c) is expressed only when Mycobacteria cells are actively dividing. By virtue of this relatively unique expression profile, Rv1980c is currently under phase III clinical trials to evaluate its potential to replace tuberculin, or purified protein derivative, as the rapid diagnostic of choice for detection of active tuberculosis infection. We describe here the NMR solution structure of Rv1980c. This structure reveals a previously undescribed fold that is based upon a variation of a beta-grasp motif most commonly found in protein-protein interaction domains. Examination of this structure in conjunction with multiple sequence alignments of MPT64 homologs identifies a candidate ligand-binding site, which may help guide future studies of Rv1980c function. The work presented here also suggests structure-based approaches for increasing the antigenic potency of a Rv1980c-based diagnostic.
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Affiliation(s)
- Zhonghua Wang
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110-2499, USA
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11
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Vipond J, Clark SO, Hatch GJ, Vipond R, Marie Agger E, Tree JA, Williams A, Marsh PD. Re-formulation of selected DNA vaccine candidates and their evaluation as protein vaccines using a guinea pig aerosol infection model of tuberculosis. Tuberculosis (Edinb) 2006; 86:218-24. [PMID: 16520093 DOI: 10.1016/j.tube.2006.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Accepted: 01/20/2006] [Indexed: 10/24/2022]
Abstract
A selection of previously identified protective Mycobacterium tuberculosis DNA vaccines were re-formulated as proteins and administered with a Th1-inducing adjuvant to help stimulate the relevant immune responses necessary for protection. All three candidate-vaccines conferred high levels of antigen-specific cellular and humoral responses, as indicated by lymphocyte proliferation and serum IgG levels. Protective efficacy was also assessed in comparison with the current vaccine, BCG (the 'gold-standard' against which new vaccines are tested), and a saline (negative) control. One candidate (Rv1806-1807) induced protection in the guinea pig aerosol infection model 30 days post-challenge on the basis of reducing the bacterial burden of M. tuberculosis in the lungs.
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MESH Headings
- Adjuvants, Immunologic
- Animals
- Antibodies, Bacterial/blood
- Antigens, Bacterial/immunology
- Cell Proliferation
- Cells, Cultured
- Disease Models, Animal
- Epitopes
- Escherichia coli/genetics
- Female
- Genes, Bacterial
- Genetic Vectors
- Guinea Pigs
- Immunity, Cellular
- Immunoglobulin G/blood
- Lung/microbiology
- Mycobacterium tuberculosis/genetics
- Mycobacterium tuberculosis/immunology
- Mycobacterium tuberculosis/isolation & purification
- Th1 Cells/immunology
- Tuberculosis Vaccines/administration & dosage
- Tuberculosis Vaccines/immunology
- Tuberculosis, Pulmonary/immunology
- Tuberculosis, Pulmonary/prevention & control
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
- Vaccines, Subunit/administration & dosage
- Vaccines, Subunit/immunology
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Affiliation(s)
- Julia Vipond
- Research Division, Health Protection Agency, Salisbury, UK.
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12
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Cai H, Tian X, Hu XD, Li SX, Yu DH, Zhu YX. Combined DNA vaccines formulated either in DDA or in saline protect cattle from Mycobacterium bovis infection. Vaccine 2005; 23:3887-95. [PMID: 15917109 DOI: 10.1016/j.vaccine.2005.03.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Revised: 03/23/2005] [Accepted: 03/26/2005] [Indexed: 11/20/2022]
Abstract
We tested the effectiveness of combined DNA vaccines encoding antigens Ag85B, MPT64 and MPT83 from Mycobacterium tuberculosis on cattle. Our results showed that calves treated with combined DNA vaccines in the presence of dimethyldioctyldecyl ammonium bromide (DDA) or saline elicited a strong gamma interferon (IFN-gamma) response 1 or 2 months after the third vaccination. All three antigens induced substantial levels of IFN-gamma production 1 month after the bacterial challenge, when the BCG-driven IFN-gamma levels dropped to less than one third of their peak values. Animals receiving combined DNA vaccines produced highest amounts of IgG antibody titer 2 months after the third vaccination. Steady state low IgG levels were found 2 months after bacterial challenge. A few small lung and lymph node lesions were detected in 1/5 animals treated with combined DNA vaccines, whereas 3/5 of BCG-treated and 5/5 of vector-control calves showed larger and significantly more lesions. About 70- to 100-fold fewer bacteria were found in the lungs and lymph nodes of combined DNA vaccine-treated animals compared to those of the control group. Histopathological analyses showed that vaccinated calves possessed substantially improved post-infection lung and lymph node pathology relative to the controls. Our data indicate that combined DNA vaccines may be used in cattle to combat bovine tuberculosis.
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Affiliation(s)
- H Cai
- National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing 100871, China.
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Weldingh K, Rosenkrands I, Okkels LM, Doherty TM, Andersen P. Assessing the serodiagnostic potential of 35 Mycobacterium tuberculosis proteins and identification of four novel serological antigens. J Clin Microbiol 2005; 43:57-65. [PMID: 15634951 PMCID: PMC540170 DOI: 10.1128/jcm.43.1.57-65.2005] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Improved diagnostic reagents are needed for the detection of Mycobacterium tuberculosis infections, and the development of a serodiagnostic test would complement presently available diagnostic methods. The aim of the present study was to identify novel serological targets for use for the future serodiagnosis of tuberculosis (TB). We cloned and expressed 35 M. tuberculosis proteins as recombinant proteins in Escherichia coli and analyzed their serodiagnostic potentials. By a two-step selection process, four superior seroantigens, TB9.7, TB15.3, TB16.3, and TB51, were identified, none of which has been described before. The four novel antigens were tested with panels of sera from smear-positive and smear-negative TB patients from areas both where TB is endemic and where TB is not endemic, with recognition frequencies ranging from 31 to 93% and with a specificity of at least 97%. The single most potent antigen was TB16.3, which had a sensitivity of 48 to 55% with samples from Danish resident TB patients and a sensitivity of 88 to 98% with samples from African TB patients. Importantly, the TB16.3 and the TB9.7 antigens were recognized by more than 85% of the samples from TB patients coinfected with human immunodeficiency virus, a patient group for which it is in general difficult to detect M. tuberculosis-specific antibodies.
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Affiliation(s)
- Karin Weldingh
- Department of Infectious Disease Immunology, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen S, Denmark.
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Ahmad S, Ali MM, Mustafa AS. Construction of a modified vector for efficient purification of recombinant Mycobacterium tuberculosis proteins expressed in Escherichia coli. Protein Expr Purif 2003; 29:167-75. [PMID: 12767806 DOI: 10.1016/s1046-5928(03)00052-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A major problem in assessing the vaccine and diagnostic potential of various proteins encoded by Mycobacterium tuberculosis genome is the inability to produce large quantities of these proteins, even when Escherichia coli or other heterologous systems are employed for recombinant protein production. To overcome these barriers, we have constructed a modified expression vector, using pGEX-4T-1 vector as the backbone. In addition to the features offered by the pGEX-4T vectors, the new vector allowed easy purification of recombinant proteins on the highly versatile Ni-NTA-agarose affinity matrix. The utility of the new vector was demonstrated by expressing and purifying, to near homogeneity, two M. tuberculosis proteins, i.e., Rv3872 (a member of the multi-gene PE subfamily) and Rv3873 (a member of the multi-gene PPE subfamily), which are encoded by the RD1 region of M. tuberculosis. The proteins encoded by rv3872 and rv3873 were expressed at high levels as fusion proteins with glutathione-S-transferase in E. coli. The recombinant Rv3872 and Rv3873 proteins were purified and isolated free of the fusion partner (GST) by affinity purification on glutathione-Sepharose and/or Ni-NTA-agarose affinity matrix and cleavage of the purified fusion proteins by thrombin protease. The recombinant Rv3872 protein was nearly homogeneous (more than 95% pure) while Rv3873 preparation was more than 90% pure. The recombinant Rv3872 and Rv3873 proteins were immunologically active and reacted with antibodies in sera from TB patients. Our results demonstrate the utility of the newly constructed expression vector with two affinity tags for efficient expression and purification of recombinant M. tuberculosis proteins expressed in E. coli, which could be used for further diagnostic and immunological studies.
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Affiliation(s)
- Suhail Ahmad
- Department of Microbiology, Faculty of Medicine, Kuwait University, P.O. Box 24923, Safat 13110, Kuwait.
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Pollock JM, McNair J, Bassett H, Cassidy JP, Costello E, Aggerbeck H, Rosenkrands I, Andersen P. Specific delayed-type hypersensitivity responses to ESAT-6 identify tuberculosis-infected cattle. J Clin Microbiol 2003; 41:1856-60. [PMID: 12734217 PMCID: PMC154711 DOI: 10.1128/jcm.41.5.1856-1860.2003] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human and bovine tuberculosis have long been detected by skin testing with purified protein derivative (PPD), a complex mix of partly denatured mycobacterial antigens with suboptimal specificity. In the present study, skin tests based on ESAT-6, a recombinantly produced antigen highly specific for tuberculosis infection, were investigated. Although ESAT-6 was strongly recognized in vitro and induced high levels of gamma interferon, initial investigations demonstrated that higher doses of ESAT-6 than of PPD were needed to induce substantial delayed-type hypersensitivity reactions. Also, the kinetics of the skin test response differed for the two reagents; PPD showed maximal response at 72 h, but the response to ESAT-6 often peaked later at 96 h. Tests based on an optimized strategy (400 micro g of ESAT-6 measured between 72 and 96 h), in cattle infected with Mycobacterium bovis (n = 22) and animals sensitized by exposure to environmental mycobacteria showed ESAT-6 to have a promising diagnostic potential (sensitivity, 82%; specificity, 100%; optimal cutoff, 3 mm), compared with PPD (sensitivity, 86%; specificity, 90%; optimal cutoff, 4 mm). Larger investigations are required to refine cutoff points for any new diagnostic test, but the present results indicate great potential for skin tests based on specific antigens for accurate in vivo diagnosis of tuberculosis.
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Affiliation(s)
- J M Pollock
- Veterinary Sciences Division, Department of Agriculture and Rural Development, Belfast, United Kingdom.
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16
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Welsh MD, Kennedy HE, Smyth AJ, Girvin RM, Andersen P, Pollock JM. Responses of bovine WC1(+) gammadelta T cells to protein and nonprotein antigens of Mycobacterium bovis. Infect Immun 2002; 70:6114-20. [PMID: 12379688 PMCID: PMC130436 DOI: 10.1128/iai.70.11.6114-6120.2002] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
WC1(+) gammadelta T cells of Mycobacterium bovis-infected cattle are highly responsive to M. bovis sonic extract (MBSE). In mycobacterial infections of other species, gammadelta T cells have been shown to respond to protein and nonprotein antigens, but the bovine WC1(+) gammadelta T-cell antigenic targets within MBSE require further definition in terms of the dominance of protein versus nonprotein components. The present study sought to characterize the WC1(+) gammadelta T-cell antigenic targets, together with the role of interleukin-2 (IL-2), in the context of M. bovis infection. This was achieved by testing crude and defined antigens to assess protein versus nonprotein recognition by WC1(+) gammadelta T cells in comparison with CD4(+) alphabeta T cells. Both cell types proliferated strongly in response to MBSE, with CD4(+) T cells being the major producers of gamma interferon (IFN-gamma). However, enzymatic digestion of the protein in MBSE removed its ability to stimulate CD4(+) T-cell responses, whereas some WC1(+) gammadelta T-cell proliferation remained. The most antigenic protein inducing proliferation and IFN-gamma secretion in WC1(+) gammadelta T-cell cultures was found to be ESAT-6, which is a potential novel diagnostic reagent and vaccine candidate. In addition, WC1(+) gammadelta T-cell proliferation was observed in response to stimulation with prenyl pyrophosphate antigens (isopentenyl pyrophosphate and monomethyl phosphate). High levels of cellular activation (CD25 expression) resulted from MBSE stimulation of WC1(+) gammadelta T cells from infected animals. A similar degree of activation was induced by IL-2 alone, but for WC1(+) gammadelta T-cell division IL-2 was found to act only as a costimulatory signal, enhancing antigen-driven responses. Overall, the data indicate that protein antigens are important stimulators of WC1(+) gammadelta T-cell proliferation and IFN-gamma secretion in M. bovis infection, with nonprotein antigens inducing significant proliferation. These findings have important implications for diagnostic and vaccine development.
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Affiliation(s)
- Michael D Welsh
- Veterinary Sciences Division, The Department of Agriculture and Rural Development, Queen's University of Belfast, Stormont, Belfast BT4 3SD, United Kingdom.
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17
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Abstract
The PE multigene family of Mycobacterium tuberculosis is remarkable in that it is composed of approximately 100 highly homologous genes that are found only in mycobacteria. Early evidence suggests that proteins encoded by certain members of this gene family could be present in the mycobacterial cell wall, impact antigen-presentation pathways and the ensuing host immune responses, and also provide a mechanism for generating antigenic diversity in mycobacteria.
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Affiliation(s)
- Michael J Brennan
- Laboratory of Mycobacterial Diseases and Cellular Immunology, Center for Biologics Evaluation and Research, Food and Drug Administration, Building 29 Room 502, 29 Lincoln Drive, Bethesda, MD 20892, USA.
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18
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Delogu G, Brennan MJ. Comparative immune response to PE and PE_PGRS antigens of Mycobacterium tuberculosis. Infect Immun 2001; 69:5606-11. [PMID: 11500435 PMCID: PMC98675 DOI: 10.1128/iai.69.9.5606-5611.2001] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sequencing of the entire genome of Mycobacterium tuberculosis identified a novel multigene family composed of two closely related subfamilies designated PE and PE_PGRS. The major difference between these two families is the presence of a domain containing numerous Gly-Ala repeats extending to the C terminus of the PE_PGRS genes. We have used a representative PE_PGRS gene from M. tuberculosis, Rv1818c (1818PE_PGRS), and its amino-terminal PE region (1818PE), to investigate the immunological response to these proteins during experimental tuberculosis and following immunization with DNA constructs. During infection of mice with M. tuberculosis, a significant humoral immune response was observed against recombinant 1818PE_PGRS but not toward the 1818PE protein. Similarly, immunization with a 1818PE_PGRS DNA construct induced antibodies directed against 1818PE_PGRS but not against 1818PE proteins, and no humoral response was induced by 1818PE DNA. These results suggest that certain PE_PGRS genes are expressed during infection of the host with M. tuberculosis and that an antibody response is directed solely against the Gly-Ala-rich PGRS domain. Conversely, splenocytes from 1818PE-vaccinated mice but not mice immunized with 1818PE_PGRS secreted gamma interferon following in vitro restimulation and demonstrated protection in the mouse tuberculosis challenge model. These results suggest that the PE vaccine can elicit an effective cellular immune response and that immune recognition of the PE antigen is influenced by the Gly-Ala-rich PGRS domain.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Bacterial/blood
- Antigens, Bacterial/chemistry
- Antigens, Bacterial/genetics
- Antigens, Bacterial/immunology
- BCG Vaccine/administration & dosage
- BCG Vaccine/immunology
- Bacterial Proteins/chemistry
- Bacterial Proteins/genetics
- Bacterial Proteins/immunology
- Disease Models, Animal
- Female
- Genes, Bacterial
- Humans
- Mice
- Molecular Sequence Data
- Multigene Family
- Mycobacterium tuberculosis/immunology
- Tuberculosis, Pulmonary/immunology
- Tuberculosis, Pulmonary/prevention & control
- Vaccination
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
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Affiliation(s)
- G Delogu
- Laboratory of Mycobacterial Diseases and Cellular Immunology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA
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19
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De Groot AS, Bosma A, Chinai N, Frost J, Jesdale BM, Gonzalez MA, Martin W, Saint-Aubin C. From genome to vaccine: in silico predictions, ex vivo verification. Vaccine 2001; 19:4385-95. [PMID: 11483263 DOI: 10.1016/s0264-410x(01)00145-1] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Bioinformatics tools enable researchers to move rapidly from genome sequence to vaccine design. EpiMer and EpiMatrix are computer-driven pattern-matching algorithms that identify T cell epitopes. Conservatrix, BlastiMer, and Patent-Blast permit the analysis of protein sequences for highly conserved regions, for homology with other known proteins, and for homology with previously patented epitopes, respectively. Two applications of these tools to epitope-driven vaccine design are described in this review. Using Conservatrix and EpiMatrix, we analyzed more than 10000 HIV-1 sequences and identified peptides that were potentially immunostimulatory and highly conserved across HIV-1 clades. MHC binding assays and CTL assays have been carried out: 50 (69%) of the 72 candidate epitopes bound in assays with cell lines expressing the corresponding MHC molecule; 15 of the 24 B7 peptides (63%) stimulated gamma-interferon release in ELISpot assays. These results lend support to the bioinformatics approach to selecting novel, conserved, HIV-1 CTL epitopes. EpiMatrix was also applied to the entire 'proteome' derived from two Mycobacterium tuberculosis (Mtb) genomes. Using EpiMatrix, BlastiMer, and Patent-Blast, we narrowed the list of putative Mtb epitopes to be tested in vitro from 1600000 to 3000, a 99.8% reduction. The pace of vaccine design will accelerate when these and other bioinformatics tools are systematically applied to whole genomes and used in combination with in vitro methods for screening and confirming epitopes.
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Affiliation(s)
- A S De Groot
- TB/HIV Research Laboratory, Brown University, Providence RI 02912, USA.
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20
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Feng CG, Demangel C, Kamath AT, Macdonald M, Britton WJ. Dendritic cells infected with Mycobacterium bovis bacillus Calmette Guerin activate CD8(+) T cells with specificity for a novel mycobacterial epitope. Int Immunol 2001; 13:451-8. [PMID: 11282984 DOI: 10.1093/intimm/13.4.451] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Although CD4(+) T cells are essential for protective immunity against Mycobacterium tuberculosis infection, recent reports indicate that CD8(+) T cells may also play a critical role in the control of this infection. However, the epitope specificity and the mechanisms of activation of mycobacteria-reactive CD8(+) T cells are poorly characterized. In order to study the CD8(+) T cell responses to the model mycobacterial antigen, MPT64, we used recombinant vaccinia virus expressing MPT64 (VVWR-64) and a panel of MPT64-derived peptides to establish that the peptide MPT64(190-198) contains an H-2D(b)-restricted CD8(+) T cell epitope. A cytotoxic T lymphocyte response to this peptide could be demonstrated in M. bovis bacillus Calmette Guerin (BCG)-infected mice following repeated in vitro stimulation. When bone marrow-derived dendritic cells (DC) were infected with BCG, the expression of MHC class I molecules by DC was up-regulated in parallel with MHC class II and B7-2, whereas CD1d expression level was not modified. Moreover, BCG-infected DC activated MPT64(190-198)-specific CD8(+) T cells to secrete IFN-gamma, although with a lower efficacy than VVWR-64-infected DC. The production of IFN-gamma by MPT64(190-198)-specific CD8(+) T cells was inhibited by antibodies to MHC class I, but not to CD1d. These data suggest that mycobacteria-specific CD8(+) T cells are primed during infection. Therefore, anti-mycobacterial vaccine strategies targeting the activation of specific CD8(+) T cells by DC may have improved protective efficacy.
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Affiliation(s)
- C G Feng
- Centenary Institute of Cancer Medicine and Cell Biology, Locked Bag No. 6, Newtown, NSW 2042, Australia
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21
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Abstract
Evaluation of new vaccines against tuberculosis requires diagnostic tools for accurately identifying asymptomatic individuals infected with Mycobacterium tuberculosis and persons with active tuberculosis. This article discusses limitations of current methods for the immunologic diagnosis of latent infection and active disease and presents novel approaches to developing skin tests and serodiagnostic assays based on "cocktails" of multiple antigens of M. tuberculosis.
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Affiliation(s)
- M L Gennaro
- Public Health Research Institute, New York, NY 10016, USA.
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22
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Musser JM, Amin A, Ramaswamy S. Negligible genetic diversity of mycobacterium tuberculosis host immune system protein targets: evidence of limited selective pressure. Genetics 2000; 155:7-16. [PMID: 10790380 PMCID: PMC1461055 DOI: 10.1093/genetics/155.1.7] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A common theme in medical microbiology is that the amount of amino acid sequence variation in proteins that are targets of the host immune system greatly exceeds that found in metabolic enzymes or other housekeeping proteins. Twenty-four Mycobacterium tuberculosis genes coding for targets of the host immune system were sequenced in 16 strains representing the breadth of genomic diversity in the species. Of the 24 genes, 19 were invariant and only six polymorphic nucleotide sites were identified in the 5 genes that did have variation. The results document the highly unusual circumstance that prominent M. tuberculosis antigenic proteins have negligible structural variation worldwide. The data are best explained by a combination of three factors: (i) evolutionarily recent global dissemination in humans, (ii) lengthy intracellular quiescence, and (iii) active replication in relatively few fully immunocompetent hosts. The very low level of amino acid diversity in antigenic proteins may be cause for optimism in the difficult fight to control global tuberculosis.
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Affiliation(s)
- J M Musser
- Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, USA.
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23
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Rosenkrands I, Weldingh K, Jacobsen S, Hansen CV, Florio W, Gianetri I, Andersen P. Mapping and identification of Mycobacterium tuberculosis proteins by two-dimensional gel electrophoresis, microsequencing and immunodetection. Electrophoresis 2000; 21:935-48. [PMID: 10768780 DOI: 10.1002/(sici)1522-2683(20000301)21:5<935::aid-elps935>3.0.co;2-p] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Mycobacterium tuberculosis is the infectious agent giving rise to human tuberculosis. The entire genome of M. tuberculosis, comprising approximately 4000 open reading frames, has been sequenced. The huge amount of information released from this project has facilitated proteome analysis of M. tuberculosis. Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was applied to fractions derived from M. tuberculosis culture filtrate, cell wall, and cytosol, resulting in the resolution of 376, 413, and 395 spots, respectively, in silver-stained gels. By microsequencing and immunodetection, 38 culture filtrate proteins were identified and mapped, of which 12 were identified for the first time. In the same manner, 23 cell wall proteins and 19 cytosol proteins were identified and mapped, with 9 and 10, respectively, being novel proteins. One of the novel proteins was not predicted in the genome project, and for four of the identified proteins alternative start codons were suggested. Fourteen of the culture filtrate proteins were proposed to possess signal sequences. Seven of these proteins were microsequenced and the N-terminal sequences obtained confirmed the prediction. The data presented here are an important complement to the genetic information, and the established 2-D PAGE maps (also available at: www.ssi.dk/publichealth/tbimmun) provide a basis for comparative studies of protein expression.
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Affiliation(s)
- I Rosenkrands
- Department of TB Immunology, Statens Serum Institute, Copenhagen, Denmark
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24
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van Pinxteren LA, Ravn P, Agger EM, Pollock J, Andersen P. Diagnosis of tuberculosis based on the two specific antigens ESAT-6 and CFP10. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2000; 7:155-60. [PMID: 10702486 PMCID: PMC95842 DOI: 10.1128/cdli.7.2.155-160.2000] [Citation(s) in RCA: 245] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tests based on tuberculin purified protein derivative (PPD) cannot distinguish between tuberculosis infection, Mycobacterium bovis BCG vaccination, or exposure to environmental mycobacteria. The present study investigated the diagnostic potential of two Mycobacterium tuberculosis-specific antigens (ESAT-6 and CFP10) in experimental animals as well as during natural infection in humans and cattle. Both antigens were frequently recognized in vivo and in vitro based on the induction of delayed-type hypersensitivity responses and the ability to induce gamma interferon production by lymphocytes, respectively. The combination of ESAT-6 and CFP10 was found to be highly sensitive and specific for both in vivo and in vitro diagnosis. In humans, the combination had a high sensitivity (73%) and a much higher specificity (93%) than PPD (7%).
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Affiliation(s)
- L A van Pinxteren
- Department of TB-Immunology, Statens Serum Institut, Copenhagen, Denmark
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25
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Abstract
Identification and characterization of mycobacterial adhesins and complementary host receptors required for colonization and dissemination of mycobacteria in host tissues are needed for a more complete understanding of the pathogenesis of diseases caused by these bacteria and for the development of effective vaccines. Previous investigations have demonstrated that a 28-kDa heparin-binding mycobacterial surface protein, HBHA, can agglutinate erythrocytes and promote mycobacterial aggregation in vitro. In this study, further molecular and biochemical analysis of HBHA demonstrates that it has three functional domains: a transmembrane domain of 18 amino acids residing near the N terminus, a large domain of 81 amino acids consistent with an alpha-helical coiled-coil region, and a Lys-Pro-Ala-rich C-terminal domain that mediates binding to proteoglycans. Using His-tagged recombinant HBHA proteins and nickel chromatography we demonstrate that HBHA polypeptides which contain the coiled-coil region form multimers. This tendency to oligomerize may be responsible for the induction of mycobacterial aggregation since a truncated N-terminal HBHA fragment containing the coiled-coil domain promotes mycobacterial aggregation. Conversely, a truncated C-terminal HBHA fragment which contains Lys-Pro-Ala-rich repeats binds to the proteoglycan decorin. These results indicate that HBHA contains at least three distinct domains which facilitate intercalation into surface membranes, promote bacterium-bacterium interactions, and mediate the attachment to sulfated glycoconjugates found in host tissues.
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Affiliation(s)
- G Delogu
- Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA
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26
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Rosenkrands I, Weldingh K, Ravn P, Brandt L, Højrup P, Rasmussen PB, Coates AR, Singh M, Mascagni P, Andersen P. Differential T-cell recognition of native and recombinant Mycobacterium tuberculosis GroES. Infect Immun 1999; 67:5552-8. [PMID: 10531199 PMCID: PMC96925 DOI: 10.1128/iai.67.11.5552-5558.1999] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium tuberculosis GroES was purified from culture filtrate, and its identity was confirmed by immunoblot analysis and N-terminal sequencing. Comparing the immunological recognition of native and recombinant GroES, we found that whereas native GroES elicited a strong proliferative response and release of gamma interferon-gamma by peripheral blood mononuclear cells from healthy tuberculin reactors, the recombinant protein failed to do so. The same difference in immunological recognition was observed in a mouse model of TB infection. Both the native and recombinant preparations were recognized by mice immunized with the recombinant protein. Biochemical characterization including sodium dodecyl sulfate-polyacrylamide gel electrophoresis, two-dimensional electrophoresis, and mass spectrometry analysis of both proteins demonstrated no differences between the native and recombinant forms of GroES except for the eight additional N-terminal amino acids derived from the fusion partner in recombinant GroES. The recombinant fusion protein, still tagged with the maltose binding protein, was recognized by T cells isolated from TB-infected mice if mixed with culture filtrate before affinity purification on an amylose column. The maltose binding protein treated in the same manner as a control preparation was not recognized. Based on the data presented, we suggest that the association of biologically active molecules from culture filtrate with the chaperone GroES may be responsible for the observed T-cell recognition of the native preparation.
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Affiliation(s)
- I Rosenkrands
- Department of TB Immunology, Statens Serum Institut, Copenhagen, Odense, Denmark
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27
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Mustafa AS, Amoudy HA, Wiker HG, Abal AT, Ravn P, Oftung F, Andersen P. Comparison of antigen-specific T-cell responses of tuberculosis patients using complex or single antigens of Mycobacterium tuberculosis. Scand J Immunol 1998; 48:535-43. [PMID: 9822264 DOI: 10.1046/j.1365-3083.1998.00419.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have screened peripheral blood mononuclear cells (PBMC) from tuberculosis (TB) patients for proliferative reactivity and interferon-gamma (IFN-gamma) secretion against a panel of purified recombinant (r) and natural (n) culture filtrate (rESAT-6, nMPT59, nMPT64 and nMPB70) and somatic-derived (rGroES, rPstS, rGroEL and rDnaK) antigens of Mycobacterium tuberculosis. The responses of PBMC to these defined antigens were compared with the corresponding results obtained with complex antigens, such as whole-cell M. tuberculosis, M. tuberculosis culture filtrate (MT-CF) and cell wall antigens, as well as the vaccine strain, Mycobacterium bovis bacillus Calmette-Guerin (BCG). In addition, M. tuberculosis and MT-CF-induced T-cell lines were tested in the same assays against the panel of purified and complex antigens. The compiled data from PBMC and T-cell lines tested for antigen-induced proliferation and IFN-gamma secretion showed that the most frequently recognized antigen was ESAT-6, followed by MPT59, GroES, MPB70, MPT64, DnaK, GroEL and PstS. The frequency of ESAT-6 responders, as measured both by proliferation (18/19) and secretion of IFN-gamma (16/19) was comparable to the results obtained with whole-cell M. tuberculosis, MT-CF and M. bovis BCG. We also observed that most of the high responders to complex antigens recognized all of the antigens tested (covariation), demonstrating that the repertoire of human T-cell specificities induced by natural infection is directed towards several unrelated culture filtrate as well as somatic-derived protein antigens. In conclusion, the results obtained suggest that the cellular immune response in humans is directed against several important target antigens of M. tuberculosis and that some antigens, such as ESAT-6, are recognized by a high number of individuals. Such antigens represent candidates to be used for development of specific diagnostic reagents or in subunit vaccines.
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Affiliation(s)
- A S Mustafa
- Department of Microbiology, Faculty of Medicine, Kuwait University, Safat
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28
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Wilkinson RJ, Wilkinson KA, De Smet KA, Haslov K, Pasvol G, Singh M, Svarcova I, Ivanyi J. Human T- and B-cell reactivity to the 16kDa alpha-crystallin protein of Mycobacterium tuberculosis. Scand J Immunol 1998; 48:403-9. [PMID: 9790311 DOI: 10.1046/j.1365-3083.1998.00420.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The attributes of immunodominance, predominant expression during mycobacterial dormancy and restriction to the Mycobacterium tuberculosis complex make the 16 kDa protein an important candidate for the study of the immune response in humans. We therefore investigated the relationship between T- and B-cell reactivity to the recombinant antigen and disease in a total of 127 subjects. The percentage of T-cell responders towards both the intact antigen and its permissively recognised peptide 16p91-110 was highest in healthy bacillus Calmette-Guérin (BCG)-sensitized controls (96% and 68%, respectively) and lowest in those with extensive untreated tuberculosis (26% and 18%) (P < 0.001). By contrast, antibody levels (ABT50 > 100) were highest in patients with extensive disease (46-50%) (P < 0.005). There was significantly higher production of IFN-gamma in the BCG-sensitized controls by comparison with untreated patients (P < 0.05), but complete antituberculous chemotherapy abolished this deficit in patients. The significance of these findings to immunodiagnosis and protective immunity is discussed.
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Affiliation(s)
- R J Wilkinson
- Wellcome Centre for Clinical Tropical Medicine, Imperial College School of Medicine, Northwick Park Hospital, Harrow, UK
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29
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Coler RN, Skeiky YAW, Vedvick T, Bement T, Ovendale P, Campos-Neto A, Alderson MR, Reed SG. Molecular Cloning and Immunologic Reactivity of a Novel Low Molecular Mass Antigen of Mycobacterium tuberculosis. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.161.5.2356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Polypeptide Ags present in the culture filtrate of Mycobacterium tuberculosis were purified and evaluated for their ability to stimulate PBMC from purified protein derivative (PPD)-positive healthy donors. One such Ag, which elicited strong proliferation and IFN-γ production, was further characterized. The N-terminal amino acid sequence of this polypeptide was determined and used to design oligonucleotides for screening a recombinant M. tuberculosis genomic DNA library. The gene (Mtb 8.4) corresponding to the identified polypeptide was cloned, sequenced, and expressed in Escherichia coli. The predicted m.w. of the recombinant protein without its signal peptide was 8.4 kDa. By Southern analysis, the DNA encoding this mycobacterial protein was found in the M. tuberculosis substrains H37Rv, H37Ra, Erdman, and “C” strain, as well as in certain other mycobacterial species, including Mycobacterium avium and Mycobacterium bovis BCG (bacillus Calmette-Guérin, Pasteur). The Mtb 8.4 gene appears to be absent from the environmental mycobacterial species examined thus far, including Mycobacterium smegmatis, Mycobacterium gordonae, Mycobacterium chelonae, Mycobacterium fortuitum, and Mycobacterium scrofulaceum. Recombinant Mtb 8.4 Ag induced significant proliferation as well as production of IFN-γ, IL-10, and TNF-α, but not IL-5, from human PBMC isolated from PPD-positive healthy donors. Mtb 8.4 did not stimulate PBMC from PPD-negative donors. Furthermore, immunogenicity studies in mice indicate that Mtb 8.4 elicits a Th1 cytokine profile, which is considered important for protective immunity to tuberculosis. Collectively, these results demonstrate that Mtb 8.4 is an immunodominant T cell Ag of M. tuberculosis.
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Affiliation(s)
- Rhea N. Coler
- *Department of Pathobiology, University of Washington, Seattle, WA 98195; and
- †Infectious Disease Research Institute and
| | | | | | | | | | | | | | - Steven G. Reed
- *Department of Pathobiology, University of Washington, Seattle, WA 98195; and
- †Infectious Disease Research Institute and
- ‡CORIXA Corporation, Seattle, WA 98104
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30
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Lyashchenko K, Manca C, Colangeli R, Heijbel A, Williams A, Gennaro ML. Use of Mycobacterium tuberculosis complex-specific antigen cocktails for a skin test specific for tuberculosis. Infect Immun 1998; 66:3606-10. [PMID: 9673239 PMCID: PMC108392 DOI: 10.1128/iai.66.8.3606-3610.1998] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The tuberculin skin test currently used to diagnose infection with Mycobacterium tuberculosis has poor diagnostic value, especially in geographic areas where the prevalence of tuberculosis is low or where the environmental burden of saprophytic, nontuberculous mycobacteria is high. Inaccuracy of the tuberculin skin test often reflects a low diagnostic specificity due to the presence in tuberculin of antigens shared by many mycobacterial species. Thus, a skin test specific for tuberculosis requires the development of new tuberculins consisting of antigens specific to M. tuberculosis. We have formulated cocktails of two to eight antigens of M. tuberculosis purified from recombinant Escherichia coli. Multiantigen cocktails were evaluated by skin testing guinea pigs sensitized with M. bovis BCG. Reactivity of multiantigen cocktails was greater than that of any single antigen. Cocktail activity increased with the number of antigens in the cocktail even when the same amount of total protein was used for cocktails and for each single antigen. A cocktail of four purified antigens specific for the M. tuberculosis complex elicited skin test responses only in BCG-immunized guinea pigs, not in control animals immunized with M. avium. These findings open the way to designing a multiantigen formulation for a skin test specific for tuberculosis.
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Affiliation(s)
- K Lyashchenko
- Public Health Research Institute, New York, New York 10016, USA
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31
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Lightbody KA, Girvin RM, Mackie DP, Neill SD, Pollock JM. T-cell recognition of mycobacterial proteins MPB70 and MPB64 in cattle immunized with antigen and infected with Mycobacterium bovis. Scand J Immunol 1998; 48:44-51. [PMID: 9714409 DOI: 10.1046/j.1365-3083.1998.00349.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Defined antigenic reagents and knowledge of T-cell responses are required for the design of improved diagnostic tests for bovine tuberculosis. The limited species distribution of Mycobacterium bovis antigens MPB70 and MPB64 has indicated their potential for inclusion in future tests. The strategy adopted in this study was to define bovine T-cell responses to these antigens at the epitope level, using cattle immunized with recombinant forms of the antigens, and to compare these responses with cattle which had been experimentally infected with M. bovis. Panels of synthetic peptides (20-mers with 10-residue overlaps) were used and five epitopes were identified and found to be powerful stimulators of T-cell responses in both types of animal (residues 81-100 and 174-190 for MPB70, and residues 1-20, 41-60 and 181-200 for MPB64). Further investigation in larger numbers of cattle (n = 14) of mixed breeds from tuberculosis-infected herds confirmed that each peptide produced response in several of the cattle, but no single peptide was recognized by all animals. However, the limited numbers of animals in this study suggest that peptide reagents may identify as many positive animals as the intact antigenic protein and could form components of a future diagnostic test. The use of cattle immunized with the proteins of interest has proved to be an interesting model for studying the nature of bovine T-cell responses to defined mycobacterial proteins.
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Affiliation(s)
- K A Lightbody
- Department of Veterinary Sciences, The Queen's University of Belfast, UK
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Elhay MJ, Oettinger T, Andersen P. Delayed-type hypersensitivity responses to ESAT-6 and MPT64 from Mycobacterium tuberculosis in the guinea pig. Infect Immun 1998; 66:3454-6. [PMID: 9632623 PMCID: PMC108370 DOI: 10.1128/iai.66.7.3454-3456.1998] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/1997] [Accepted: 04/24/1998] [Indexed: 02/07/2023] Open
Abstract
Two antigens from Mycobacterium tuberculosis, ESAT-6 and MPT64, elicited delayed-type hypersensitivity (DTH) skin responses in outbred guinea pigs infected with M. tuberculosis by the aerosol and intravenous routes but not those sensitized with M. bovis BCG or M. avium. The DTH epitope of ESAT-6 was mapped to the C terminus. Nonresponders to the individual antigens were found, but all animals responded to a combination of ESAT-6 and MPT64 or their respective minimal target peptides. Correspondingly, these molecules could form the basis of a new skin test for tuberculosis.
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Affiliation(s)
- M J Elhay
- Department of TB Immunology, Statens Serum Institut, Copenhagen, Denmark
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Manca C, Lyashchenko K, Colangeli R, Gennaro ML. MTC28, a novel 28-kilodalton proline-rich secreted antigen specific for the Mycobacterium tuberculosis complex. Infect Immun 1997; 65:4951-7. [PMID: 9393781 PMCID: PMC175714 DOI: 10.1128/iai.65.12.4951-4957.1997] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Proteins that are actively secreted by Mycobacterium tuberculosis serve as major targets of immune responses in the infected host. To identify and purify novel proteins in the filtrates of M. tuberculosis cultures, a bacteriophage lambda library of M. tuberculosis H37Rv DNA was immunoscreened by using an anti-culture filtrate rabbit antiserum. Of 20 positive clones isolated, 6 were analyzed and found to express the genes for two known components of the early culture filtrate, the secreted 45/47-kDa antigen complex and the KatG protein, and two novel genes. Here we report the molecular cloning and nucleotide sequence of one of the new genes encoding a culture filtrate protein of 310 amino acid (aa) residues. We called this gene mtc28. The deduced polypeptide sequence contained an NH2-terminal, highly hydrophobic 32-aa region having properties of a secretion signal peptide. The putative 278-aa mature MTC28 protein was characterized at its NH2 and COOH termini by a high content of proline and alanine residues organized in an (AP)n motif. Thus, MTC28 is a new member of a group of proline-rich antigens found in M. tuberculosis and Mycobacterium leprae. As shown by DNA hybridization experiments, the mtc28 gene was present only in species of the M. tuberculosis complex. Purified recombinant MTC28 antigen evoked strong delayed-type hypersensitivity and antibody responses in guinea pigs immunized with Mycobacterium bovis BCG, but not in guinea pigs immunized with Mycobacterium avium. The strong immunological activity of MTC28 and the absence of B- and T-cell epitopes cross-reactive with a common environmental mycobacterial species, such as M. avium, make this novel antigen an attractive reagent for immunodiagnosis of tuberculosis.
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Affiliation(s)
- C Manca
- Public Health Research Institute, New York, New York 10016, USA
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Pollock JM, Andersen P. Predominant recognition of the ESAT-6 protein in the first phase of interferon with Mycobacterium bovis in cattle. Infect Immun 1997; 65:2587-92. [PMID: 9199424 PMCID: PMC175366 DOI: 10.1128/iai.65.7.2587-2592.1997] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Tuberculosis continues to be a worldwide health problem for both humans and animals. The development of improved vaccines and diagnostic tests requires detailed understanding of the immune responses generated and the antigens recognized during the disease. This study examined the T-cell response which develops in cattle experimentally infected with Mycobacterium bovis. The first significant T-cell response was found 3 weeks after the onset of infection and was characterized by a pronounced gamma interferon (IFN-gamma) response from peripheral blood mononuclear cells directed to antigens in culture filtrates. Short-term culture filtrate (ST-CF) was separated into molecular mass fractions and screened for recognition by T cells from experimentally infected and field cases of bovine tuberculosis. Cattle in the early stages of experimental infection were characterized by strong IFN-gamma responses directed predominantly toward the lowest-mass (<10-kDa) fraction of ST-CF, but cattle in later stages of experimental infection (16 weeks postinfection) exhibited a broader recognition of antigens of various molecular masses. Field cases of bovine tuberculosis, in comparison, preferentially recognized low-mass antigens, characteristic of animals in the early stages of infection. The major T-cell target for this dominant IFN-gamma response was found to be the secreted antigen ESAT-6. This antigen was recognized strongly by the majority of field cases of bovine tuberculosis tested. As ESAT-6 is unique to pathogenic mycobacterial species, our study suggests that ESAT-6 is an antigen with major potential for vaccination against and specific diagnosis of bovine tuberculosis.
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Affiliation(s)
- J M Pollock
- Department of Agriculture for Northern Ireland, Stormont, Belfast, United Kingdom
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Shirakawa T, Enomoto T, Shimazu S, Hopkin JM. The inverse association between tuberculin responses and atopic disorder. Science 1997; 275:77-9. [PMID: 8974396 DOI: 10.1126/science.275.5296.77] [Citation(s) in RCA: 985] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Human immune responses are heterogeneous and may involve antagonism between T helper (TH) lymphocyte subsets and their cytokines. Atopy is characterized by immediate immunoglobulin E (IgE)-mediated hypersensitivity to agents such as dust mites and pollen, and it underlies the increasingly prevalent disorder asthma. Among Japanese schoolchildren, there was a strong inverse association between delayed hypersensitivity to Mycobacterium tuberculosis and atopy. Positive tuberculin responses predicted a lower incidence of asthma, lower serum IgE levels, and cytokine profiles biased toward TH1 type. Exposure and response to M. tuberculosis may, by modification of immune profiles, inhibit atopic disorder.
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Affiliation(s)
- T Shirakawa
- Lung Research Laboratory, Osler Chest Unit, Churchill Hospital, Oxford OX3 7LJ, UK.
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