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Schorey JS, Cheng Y, Singh PP, Smith VL. Exosomes and other extracellular vesicles in host-pathogen interactions. EMBO Rep 2014; 16:24-43. [PMID: 25488940 DOI: 10.15252/embr.201439363] [Citation(s) in RCA: 496] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
An effective immune response requires the engagement of host receptors by pathogen-derived molecules and the stimulation of an appropriate cellular response. Therefore, a crucial factor in our ability to control an infection is the accessibility of our immune cells to the foreign material. Exosomes-which are extracellular vesicles that function in intercellular communication-may play a key role in the dissemination of pathogen- as well as host-derived molecules during infection. In this review, we highlight the composition and function of exosomes and other extracellular vesicles produced during viral, parasitic, fungal and bacterial infections and describe how these vesicles could function to either promote or inhibit host immunity.
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Affiliation(s)
- Jeffrey S Schorey
- Department of Biological Sciences, Eck Institute for Global Health University of Notre Dame, Notre Dame, IN, USA
| | - Yong Cheng
- Department of Biological Sciences, Eck Institute for Global Health University of Notre Dame, Notre Dame, IN, USA
| | - Prachi P Singh
- Department of Biological Sciences, Eck Institute for Global Health University of Notre Dame, Notre Dame, IN, USA
| | - Victoria L Smith
- Department of Biological Sciences, Eck Institute for Global Health University of Notre Dame, Notre Dame, IN, USA
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Adlakha N, Vir P, Verma I. Effect of mycobacterial secretory proteins on the cellular integrity and cytokine profile of type II alveolar epithelial cells. Lung India 2012; 29:313-8. [PMID: 23243342 PMCID: PMC3519014 DOI: 10.4103/0970-2113.102796] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: Pulmonary tuberculosis (TB) is caused by Mycobacterium tuberculosis (M. tb). In lungs, alveolar macrophages and type II alveolar epithelial cells serve as a replicative niche for this pathogen. Secretory proteins released by actively replicating tubercle bacilli are known to interact with host cells at the initial stages of infection. To understand the role of these cells in TB pathogenesis, it is important to identify the mycobacterial components involved in interaction with alveolar epithelial cells. Materials and Methods: We fractionated the whole secretory proteome of M. tb H37Rv into 10 narrow molecular mass fractions (A1-A10; <20 kDa to >90 kDa) that were studied for their binding potential with A549; type II alveolar epithelial cell line. We also studied the consequences of this interaction in terms of change in epithelial cell viability by MTT assay and cytokine release by ELISA. Results: Our results show that several mycobacterial proteins bind and confer cytolysis in epithelial cells. Amongst all the fractions, proteins ranging from 35-45 kDa (A5) exhibited highest binding to A549 cells with a consequence of cytolysis of these cells. This fraction (A5) also led to release of various cytokines important in anti-mycobacterial immunity. Conclusion: Fraction A5 (35-45 kDa) of mycobacterial secretory proteome play an important role in mediating M. tb interaction with type II alveolar epithelial cells with the consequences detrimental for the TB pathogenesis. Further studies are being carried out to identify the candidate proteins from this region.
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Affiliation(s)
- Nidhi Adlakha
- Department of Biochemistry, TB Immunology and Cell Biology Lab, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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Duggirala S, Venu K, Subhakar K, Sritharan M. T-cell recognition of iron-regulated culture filtrate proteins of Mycobacterium tuberculosis in tuberculosis patients and endemic normal controls. Indian J Med Microbiol 2012; 30:323-31. [PMID: 22885200 DOI: 10.4103/0255-0857.99495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Culture filtrate proteins (CFPs) of Mycobacterium tuberculosis are potential vaccine candidates. OBJECTIVE The aim was to study the influence of iron levels on CFPs and assess the immuno-protective potential of defined antigenic fractions from high (8 μg Fe/mL) and low iron (0.02 μg Fe / mL) cultures of M. tuberculosis. MATERIALS AND METHODS The CFPs of M. tuberculosis from high (CFP-high) and low (CFP-low) iron conditions were first compared to identify iron-regulated proteins and then fractionated to obtain ten antigen pools (CF-Ags H1- H5 and L1-L5) that were used to assess the immune response of TB patients and normal healthy controls. RESULTS Iron limitation resulted in the up-regulation of two novel iron-regulated low-molecular-weight proteins Irp-1 (in CF-Ag L4) and Irp-2 (in CF-Ag L5) and repression of two ESAT proteins (identified with monoclonal antibody HYB 76.8). The median stimulation indices (SIs) against most of the CF-Ags were high in pulmonary TB patients. The CF-Ags L1 and L2 showed statistically significant SI (P values of 0.0027 and 0.0029 respectively); the % case recognition was high with these antigens as well as with L4 ( P = 0.0275). IFN-γ in response to these CF-Ags was significantly high in the endemic normals; maximal expression was seen with CF-Ag L5 (median value of 233 pg mL -1 ) that was higher than the corresponding H5 (140 pg mL -1 ) and H3 and L3 (205 and 206 pg mL -1 respectively). CONCLUSIONS CF-Ags L5, H3 and L3 showed immuno-protective potential in this geographical location.
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Affiliation(s)
- S Duggirala
- Department of Animal Sciences, University of Hyderabad, Andhra Pradesh, India
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Beamer GL, Cyktor J, Flaherty DK, Stromberg PC, Carruthers B, Turner J. CBA/J mice generate protective immunity to soluble Ag85 but fail to respond efficiently to Ag85 during natural Mycobacterium tuberculosis infection. Eur J Immunol 2012; 42:870-9. [PMID: 22531914 DOI: 10.1002/eji.201142054] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In CBA/J mice, susceptibility to Mycobacterium tuberculosis (M.tb) is associated with low interferon-gamma (IFN-γ) responses to antigens (Antigen 85 (Ag85) and early secreted antigenic target-6 (ESAT-6)) that have been defined as immunodominant. Here, we asked whether the failure of CBA/J mice to recognize Ag85 is a consequence of M.tb infection or whether CBA/J mice have a general defect in generating specific T-cell responses to this protein antigen. We compared CBA/J mice during primary M.tb infection, Ag85 vaccination followed by M.tb challenge, or M.tb memory immune mice for their capacity to generate Ag85-specific IFN-γ responses and to control M.tb infection. CBA/J mice did not respond efficiently to Ag85 in the context of natural infection or re-infection. In contrast, CBA/J mice could generate Ag85-specific IFN-γ responses and protective immunity when this antigen was delivered as a soluble protein. Our data indicate that although M.tb infection of CBA/J mice does not drive an Ag85 response, these mice can fully and protectively respond to Ag85 if it is delivered as a vaccine. The data from this experimental model suggest that the Ag85-containing vaccines in clinical trials should protect M.tb susceptible humans.
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Affiliation(s)
- Gillian L Beamer
- Center for Microbial Interface Biology, The Ohio State University, Columbus, OH, USA
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Legesse M, Ameni G, Mamo G, Medhin G, Bjune G, Abebe F. Performance of QuantiFERON-TB Gold In-Tube (QFTGIT) for the diagnosis of Mycobacterium tuberculosis (Mtb) infection in Afar Pastoralists, Ethiopia. BMC Infect Dis 2010; 10:354. [PMID: 21162756 PMCID: PMC3009640 DOI: 10.1186/1471-2334-10-354] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Accepted: 12/17/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Currently, T-cell based gamma interferon (IFNγ) release assays (IGRAs) are acknowledged as the best methods available for the screening of latent tuberculosis infection (LTBI) and also as aid for the diagnosis of active tuberculosis (TB). To our information, the performance of these diagnostic tests has not been evaluated in Ethiopia. Therefore, the intent of this study was to evaluate the performance of QuantiFERON-TB Gold In-Tube (QFTGIT) in patients clinically suspected of active pulmonary TB (PTB) as well as in healthy subjects prior to its utilization for the epidemiological study of active TB and LTBI in Afar pastoralists. METHODS The sensitivity of QFTGIT was evaluated in 140 subjects who were clinically suspected of PTB using the cut-off value recommended by the manufacturer (≥ 0.35 IU/ml) and disease-specific cut-off value. Sputum culture result was used as a gold standard. The specificity of the test was evaluated both in patients and in 55 tuberculin skin test (TST) negative healthy subjects. RESULTS Out of the 140 study participants, 37 (26.4%) were positive for active PTB by culture. Out of the 37 subjects who had positive results by culture, 6 individuals were HIV-seropositive. Out of the 103 subjects who were negative by culture, 6 subjects had indeterminate results and 21 were HIV-seropositive. The performance of the test was assessed using data from 107 (31 culture positive and 76 culture negative) individuals who were clinically suspected of PTB and HIV-seronegatives. Using the manufacturer recommended cut-off value, the sensitivity of the test was 64.5% (20/31), while its specificity was 36.8% (28/76). The sensitivity of the test was increased to 77.4%, while the specificity was reduced to 23.7% using a cut-off value ≥ 0.1 IU/ml of IFNγ as disease-specific cut-off value. In TST negative healthy subjects, the specificity of the test was 58.2%. CONCLUSION Our findings revealed a low sensitivity of QFTGIT in the diagnosis of Mycobacterium tuberculosis (Mtb) infection in the present study area using the cut-off value recommended by the manufacturer. Nevertheless, the sensitivity increased from 64.5% to 77.4% by lowering the cut-off value recommended by the manufacturer to ≥ 0.1 IU/ml of IFNγ level. Hence, it is of practical importance to evaluate the performance of QFTGIT in population under different settings prior to its application either for the diagnosis of active TB or LTBI.
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Affiliation(s)
- Mengistu Legesse
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- Department of General Practice and Community Medicine, Institute for Health and Society, University of Oslo, Oslo, Norway
| | - Gobena Ameni
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Gezahegne Mamo
- Faculty of Veterinary Medicine, Addis Ababa University, Bishofituu, Ethiopia
- Department of General Practice and Community Medicine, Institute for Health and Society, University of Oslo, Oslo, Norway
| | - Girmay Medhin
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Gunnar Bjune
- Department of General Practice and Community Medicine, Institute for Health and Society, University of Oslo, Oslo, Norway
| | - Fekadu Abebe
- Department of General Practice and Community Medicine, Institute for Health and Society, University of Oslo, Oslo, Norway
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Giri PK, Kruh NA, Dobos KM, Schorey JS. Proteomic analysis identifies highly antigenic proteins in exosomes from M. tuberculosis-infected and culture filtrate protein-treated macrophages. Proteomics 2010; 10:3190-202. [PMID: 20662102 PMCID: PMC3664454 DOI: 10.1002/pmic.200900840] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 05/04/2010] [Accepted: 06/15/2010] [Indexed: 12/17/2022]
Abstract
Exosomes are small 30-100 nm membrane vesicles released from hematopoietic and nonhematopoietic cells and function to promote intercellular communication. They are generated through fusion of multivesicular bodies with the plasma membrane and release of interluminal vesicles. Previous studies from our laboratory demonstrated that macrophages infected with Mycobacterium release exosomes that promote activation of both innate and acquired immune responses; however, the components present in exosomes inducing these host responses were not defined. This study used LC-MS/MS to identify 41 mycobacterial proteins present in exosomes released from M. tuberculosis-infected J774 cells. Many of these proteins have been characterized as highly immunogenic. Further, since most of the mycobacterial proteins identified are actively secreted, we hypothesized that macrophages treated with M. tuberculosis culture filtrate proteins (CFPs) would release exosomes containing mycobacterial proteins. We found 29 M. tuberculosis proteins in exosomes released from CFP-treated J774 cells, the majority of which were also present in exosomes isolated from M. tuberculosis-infected cells. The exosomes from CFP-treated J774 cells could promote macrophage and dendritic cell activation as well as activation of naïve T cells in vivo. These results suggest that exosomes containing M. tuberculosis antigens may be alternative approach to developing a tuberculosis vaccine.
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Affiliation(s)
- Pramod K. Giri
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA
- Present address:
Department of Microbiology & Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Nicole A. Kruh
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Karen M. Dobos
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Jeff S. Schorey
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA
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Eweda G, Suzuki D, Nagata T, Tsujimura K, Koide Y. Identification of murine T-cell epitopes on low-molecular-mass secretory proteins (CFP11, CFP17, and TB18.5) of Mycobacterium tuberculosis. Vaccine 2010; 28:4616-25. [PMID: 20457290 DOI: 10.1016/j.vaccine.2010.04.079] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2009] [Revised: 04/23/2010] [Accepted: 04/26/2010] [Indexed: 10/19/2022]
Abstract
The low-molecular-mass secretory proteins of Mycobacterium tuberculosis have been shown to be major T-cell antigens during infection with the pathogenic bacterium. In this study, we determined murine T-cell epitopes on three low-molecular-mass proteins, CFP11 (Rv2433c), CFP17 (Rv1827), and TB18.5 (Rv0164) using DNA immunization of inbred mice. We analyzed interferon-gamma production from immune splenocytes in response to overlapping peptides covering these proteins. We identified two CD8+ T-cell epitopes on CFP11 and CFP17, one in BALB/c mice and the other in C57BL/6 mice, respectively. On TB18.5, we identified a CD8+ T-cell epitope in BALB/c mice and a CD4+ T-cell epitope in C57BL/6 mice. With the aid of computer algorithms, we could identify the minimal CD8+ T-cell epitopes. These T-cell epitopes are feasible for analysis of the role of antigen-specific T cells during M. tuberculosis infection.
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Affiliation(s)
- Ghada Eweda
- Department of Infectious Diseases, Hamamatsu University School of Medicine, 1-20-1 Higashi-ku, Handa-yama, Hamamatsu 431-3192, Japan
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Abstract
Tuberculosis (TB) is an international public health priority and kills almost two million people annually. TB is out of control in Africa due to increasing poverty and HIV coinfection, and drug-resistant TB threatens to destabilize TB control efforts in several regions of the world. Existing diagnostic tools and therapeutic interventions for TB are suboptimal. Thus, new vaccines, immunotherapeutic interventions and diagnostic tools are urgently required to facilitate TB control efforts. An improved understanding of the immunopathogenesis of TB can facilitate the identification of correlates of immune protection, the design of effective vaccines, the rational selection of immunotherapeutic agents, the evaluation of new drug candidates, and drive the development of new immunodiagnostic tools. Here we review the immunology of TB with a focus on aspects that are clinically and therapeutically relevant. An immunologically orientated approach to tackling TB can only succeed with concurrent efforts to alleviate poverty and reduce the global burden of HIV.
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Affiliation(s)
- Keertan Dheda
- Division of Pulmonology and Clinical Immunology & UCT Lung Institute, Department of Medicine, University of Cape Town, Cape Town, South Africa.
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Deenadayalan A, Heaslip D, Rajendiran AA, Velayudham BV, Frederick S, Yang HL, Dobos K, Belisle JT, Raja A. Immunoproteomic identification of human T cell antigens of Mycobacterium tuberculosis that differentiate healthy contacts from tuberculosis patients. Mol Cell Proteomics 2009; 9:538-49. [PMID: 20031926 DOI: 10.1074/mcp.m900299-mcp200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Identification of Mycobacterium tuberculosis antigens inducing cellular immune responses is required to improve the diagnosis of and vaccine development against tuberculosis. To identify the antigens of M. tuberculosis that differentiated between tuberculosis (TB) patients and healthy contacts based on T cell reactivity, the culture filtrate of in vitro grown M. tuberculosis was fractionated by two-dimensional liquid phase electrophoresis and tested for the ability to stimulate T cells in a whole blood assay. This approach separated the culture filtrate into 350 fractions with sufficient protein quantity (at least 200 microg of protein) for mass spectrometry and immunological analyses. High levels of interferon-gamma (IFN-gamma) secretion were induced by 105 fractions in healthy contacts compared with TB patients (p < 0.05). Most interesting was the identification of 10 fractions that specifically induced strong IFN-gamma production in the healthy contact population but not in TB patients. Other immunological measurements showed 42 fractions that induced significant lymphocyte proliferative responses in the healthy contact group compared with the TB patients. The tumor necrosis factor-alpha response for most of the fractions did not significantly differ in the tested groups, and the interleukin-4 response was below the detectable range for all fractions and both study groups. Proteomic characterization of the 105 fractions that induced a significant IFN-gamma response in the healthy contacts compared with the TB patients led to the identification of 59 proteins of which 24 represented potentially novel T cell antigens. Likewise, the protein identification in the 10 healthy "contact-specific fractions" revealed 16 proteins that are key candidates as vaccine or diagnostic targets.
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Affiliation(s)
- Anbarasu Deenadayalan
- Tuberculosis Research Centre, Indian Council of Medical Research, Mayor V. R. Ramanathan Road, Chetput, Chennai 600 031, India
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Ferrara G, Losi M, Fabbri LM, Migliori GB, Richeldi L, Casali L. Exploring the immune response against Mycobacterium tuberculosis for a better diagnosis of the infection. Arch Immunol Ther Exp (Warsz) 2009; 57:425-33. [PMID: 19866341 DOI: 10.1007/s00005-009-0050-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Accepted: 04/29/2009] [Indexed: 01/18/2023]
Abstract
Tuberculosis (TB) still represents a monumental problem, with more than two million deaths every year worldwide. The current diagnostics for TB offer sub-optimal accuracy both for the active and the latent form of infection and are often based on technologies unaffordable in low-income settings. The tuberculin skin test was the first diagnostic based on an acquired immune response towards Mycobacterium tuberculosis (MTB). Advances in molecular and cellular biology and the elucidation of the mechanisms governing the relation between MTB and the human immune system form the basis for new and more accurate assays, potentially able to fill the gaps and limits of classical diagnostics. However, the process of validating new tests is still complex and hampered by specific questions regarding TB immunology and natural history. We present here a summary of the current approaches to validate new diagnostics based on the detection of immunological biomarkers of TB infection.
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Affiliation(s)
- Giovanni Ferrara
- Section of Respiratory Disease, Department of Internal Medicine, St. Maria Hospital, University of Perugia, Via T. Di Joannuccio 1, 05100 Terni, Italy.
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Luo Y, Wang B, Hu L, Yu H, Da Z, Jiang W, Song N, Qie Y, Wang H, Tang Z, Xian Q, Zhang Y, Zhu B. Fusion protein Ag85B-MPT64190–198-Mtb8.4 has higher immunogenicity than Ag85B with capacity to boost BCG-primed immunity against Mycobacterium tuberculosis in mice. Vaccine 2009; 27:6179-85. [DOI: 10.1016/j.vaccine.2009.08.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Revised: 07/27/2009] [Accepted: 08/06/2009] [Indexed: 11/24/2022]
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Perrella A, Grattacaso S, d'Antonio A, Atripaldi L, Sbreglia C, Gnarini M, Conti P, Vecchiet J, Perrella O. Evidence of hepatitis C virus-specific interferon gamma-positive T cells in health care workers in an infectious disease department. Am J Infect Control 2009; 37:426-429. [PMID: 19155099 DOI: 10.1016/j.ajic.2008.08.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 08/26/2008] [Accepted: 08/28/2008] [Indexed: 02/05/2023]
Abstract
BACKGROUND Few studies are available on possible hepatitis C virus (HCV)-specific T-cell immune response in health care workers (HCWs) involved in the care of patients with HCV infection. We aimed to investigate whether a HCV-specific interferon (IFN)-gamma T-cell response, known to be involved in infection resolution, was present in those HCWs involved in the management of patients with persistent HCV infection. METHODS Our study involved 30 subjects, classified as group A (20 consecutive patients, 16 males and 4 females, with histologically proven chronic hepatitis), or group B (10 HCWs, 7 males and 3 females, with at least 7 years of health care experience and HCV-RNA and anti-HCV negative). As a control group, we used 10 blood samples from healthy donors at a blood donor center (group C). HCV-RNA was measured by real-time polymerase chain reaction. Blood samples (at least 35 mL) were collected from all group A and group B subjects in our hospital. Specific IFN-gamma was stimulated with HCV pool peptides (core, 2 microg/mL), with influenza Mp peptides used as a positive control. RESULTS Levels of HCV-specific IFN-gamma-positive cells were higher in the HCWs (group B) compared with the infected patients (group A) and healthy blood donors (group C) (Mann-Whitney U test, P < .001). CONCLUSION A clinically silent persistent exposure to HCV, through some as-yet undetermined mechanism, may induce a virus-specific IFN-gamma-producing CD8(+) T-cell response in healthy aviremic HCWs. This finding suggests that possible unapparent parenteral routes may stimulate host defenses with no evidence of hepatitis.
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Affiliation(s)
- Alessandro Perrella
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy.
| | - Stella Grattacaso
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy
| | - Anna d'Antonio
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy
| | - Luigi Atripaldi
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy
| | - Costanza Sbreglia
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy
| | - MariaRosaria Gnarini
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy
| | - Pio Conti
- Department of Immunology, School of Medicine, G.D'Annunzio University, Chieti, Italy
| | - Jacopo Vecchiet
- Infectious Disease Department, G.D'Annunzio University, Chieti, Italy
| | - Oreste Perrella
- Department of Infectious Disease and Immunology, Hospital D. Cotugno, Naples, Italy
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Abstract
Vaccines against intracellular pathogens such as Mycobacterium tuberculosis need to induce strong cellular immune responses. Antigen discovery programs have exploited this and used proteome studies and T-cell recognition in PPD-positive individuals to select proteins and after testing for protective efficacy in animals the most promising proteins have been put together in fusion molecules. Three such fusion proteins are currently in clinical trials, the two most advanced have already passed phase I trials and are entering phase II.
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Silva VMC, Sardella IG, Luiz RR, Cunha AJLA, Cavalcanti AH, Mahavir S, Barreto MM, Rodrigues RS, Carvalho TF, Saad MHF. Immunoreactivity of five antigens ofMycobacterium tuberculosisin patients attending a public health care facility in an area with high endemicity for TB. Microbiol Immunol 2008; 52:544-50. [DOI: 10.1111/j.1348-0421.2008.00072.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Guinea pig model of Mycobacterium tuberculosis latent/dormant infection. Microbes Infect 2008; 10:1469-76. [PMID: 18817888 DOI: 10.1016/j.micinf.2008.08.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 08/20/2008] [Accepted: 08/21/2008] [Indexed: 11/23/2022]
Abstract
Although guinea pigs are considered one of the best animal models of tuberculosis, little data exist describing latent or dormant tuberculosis infection in these animals. Here we address this issue using a streptomycin auxotrophic mutant of Mycobacterium tuberculosis. This mutant grows unimpaired in the presence of streptomycin but in its absence shifts to latency/dormancy (lack growth and over-expression of alpha-crystallin). To establish infection animals are inoculated with the mutant followed by daily administration of streptomycin (three weeks), which allows initial microbial multiplication in the animal's tissues. Withdrawal of streptomycin establishes latency/dormancy and few viable organisms are recovered from the animals' lungs and spleen six months later. During the infectious process guinea pigs steadily gained weight and presented no clinical signs (scuff fur and lethargy) of disease. Histopathology of organs mimicked tuberculous lesions in humans and PBMC from infected animals strongly responded to stimulation with PPD. Finally, tuberculin skin test (a hallmark of latent infection diagnosis) performed in infected animals was strongly positive (>or=15 mm induration). These results point to an interesting and reliable model of latent/dormant tuberculosis infection in guinea pigs.
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Weir RE, Fine PEM, Floyd S, Stenson S, Stanley C, Branson K, Britton WJ, Huygen K, Singh M, Black G, Dockrell HM. Comparison of IFN-gamma responses to mycobacterial antigens as markers of response to BCG vaccination. Tuberculosis (Edinb) 2008; 88:31-8. [PMID: 18277396 DOI: 10.1016/j.tube.2007.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
An increase in interferon-gamma (IFN-gamma) production to Mycobacterium tuberculosis purified protein derivative (Mtb PPD), as measured in the cultured diluted whole blood assay, is one indicator of a protective immune response to BCG vaccine. We have explored the potential for this assay to be improved by measuring IFN-gamma responses to more defined antigens of M. tuberculosis (short-term and mid-term culture filtrates, ESAT-6, 38 kDa), Mycobacterium bovis (MPB70), M. bovis BCG (Antigen 85) and Mycobacterium leprae (35 kDa), in UK teenagers before and 1 year after BCG vaccination (or no vaccination as controls). There was a significant increase in response to the culture filtrates post-vaccination, but this was no greater than that to Mtb PPD. Many teenagers responded to the purified antigens, in particular to Antigen 85, prior to vaccination, and BCG vaccination could only augment this pre-existing response to a limited extent; prior exposure to environmental mycobacteria can thus induce cross-reactive responses to antigens which complicate interpretation of in vitro assays of vaccine response. In contrast, ESAT-6 was recognised by only one teenager prior to vaccination, and, as expected, responses were not boosted by BCG. We therefore conclude that Mtb PPD is the antigen preparation of choice for assessing the immunogenicity of BCG vaccination.
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Affiliation(s)
- Rosemary E Weir
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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Expression and purification of Mycobacterium tuberculosis ESAT-6 and MPT64 fusion protein and its immunoprophylactic potential in mouse model. Protein Expr Purif 2008; 59:189-96. [DOI: 10.1016/j.pep.2007.11.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 11/26/2007] [Accepted: 11/28/2007] [Indexed: 10/22/2022]
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Kalra M, Grover A, Mehta N, Singh J, Kaur J, Sable SB, Behera D, Sharma P, Verma I, Khuller GK. Supplementation with RD antigens enhances the protective efficacy of BCG in tuberculous mice. Clin Immunol 2007; 125:173-83. [PMID: 17766185 DOI: 10.1016/j.clim.2007.07.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 07/14/2007] [Accepted: 07/17/2007] [Indexed: 01/05/2023]
Abstract
Different combinations of ESAT-6, CFP-10, CFP-21, MPT-64, encoded by RD1 and RD2 of Mycobacterium tuberculosis were evaluated on the basis of antigenicity in PPD positive TB contacts and immunogenicity in C57BL/6J mice immunized with the combination of all four RD antigens. The peripheral blood mononuclear cells of TB contacts showed maximum recognition in response to the combination of ESAT-6+MPT-64 in terms of predominant lymphoproliferation, IFN-gamma levels and the number of responders. On the contrary, the combination of ESAT-6+CFP-21+MPT-64 was found to be most immunogenic based on both T-cell and antibody responses in immunized mice. Prophylactic potential of the selected combinations was assessed as supplementation vaccines to BCG against intravenous challenge with M. tuberculosis in mice. BCG supplementation with the selected combinations resulted in significantly greater protection as compared to BCG alone against experimental tuberculosis and thus appears to be a promising approach to enhance the protective efficacy of the existing vaccine.
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Affiliation(s)
- Mamta Kalra
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh-160012, India
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19
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Schierloh P, Yokobori N, Alemán M, Landoni V, Geffner L, Musella RM, Castagnino J, Baldini M, Abbate E, de la Barrera SS, Sasiain MC. Mycobacterium tuberculosis-induced gamma interferon production by natural killer cells requires cross talk with antigen-presenting cells involving Toll-like receptors 2 and 4 and the mannose receptor in tuberculous pleurisy. Infect Immun 2007; 75:5325-37. [PMID: 17709420 PMCID: PMC2168293 DOI: 10.1128/iai.00381-07] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tuberculous pleurisy allows the study of human cells at the site of active Mycobacterium tuberculosis infection. In this study, we found that among pleural fluid (PF) lymphocytes, natural killer (NK) cells are a major source of early gamma interferon (IFN-gamma) upon M. tuberculosis stimulation, leading us to investigate the mechanisms and molecules involved in this process. We show that the whole bacterium is the best inducer of IFN-gamma, although a high-molecular-weight fraction of culture filtrate proteins from M. tuberculosis H37Rv and the whole-cell lysate also induce its expression. The mannose receptor seems to mediate the inhibitory effect of mannosylated lipoarabinomannan, and Toll-like receptor 2 and 4 agonists activate NK cells but do not induce IFN-gamma like M. tuberculosis does. Antigen-presenting cells (APC) and NK cells bind M. tuberculosis, and although interleukin-12 is required, it is not sufficient to induce IFN-gamma expression, indicating that NK cell-APC contact takes place. Indeed, major histocompatibility complex class I, adhesion, and costimulatory molecules as well as NK receptors regulate IFN-gamma induction. The signaling pathway is partially inhibited by dexamethasone and sensitive to Ca2+ flux and cyclosporine. Inhibition of p38 and extracellular-regulated kinase mitogen-activated protein kinase pathways reduces the number of IFN-gamma+ NK cells. Phosphorylated p38 (p-p38) is detected in ex vivo PF-NK cells, and M. tuberculosis triggers p-p38 in PF-NK cells at the same time that binding between NK and M. tuberculosis reaches its maximum value. Thus, interplay between M. tuberculosis and NK cells/APC triggering IFN-gamma would be expected to play a beneficial role in tuberculous pleurisy by helping to maintain a type 1 profile.
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Affiliation(s)
- Pablo Schierloh
- Departamento de Inmunología, Instituto de Investigaciones Hematológicas, Academia Nacional de Medicina, Buenos Aires, Argentina
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20
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Sable SB, Plikaytis BB, Shinnick TM. Tuberculosis subunit vaccine development: Impact of physicochemical properties of mycobacterial test antigens. Vaccine 2007; 25:1553-66. [PMID: 17166640 DOI: 10.1016/j.vaccine.2006.11.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Revised: 09/27/2006] [Accepted: 11/07/2006] [Indexed: 11/23/2022]
Abstract
Tuberculosis caused by Mycobacterium tuberculosis continues to be one of the major public health problems in the world. The eventual control of this disease will require the development of a safe and effective vaccine. One of the approaches receiving a great deal of attention recently is subunit vaccination. An efficacious antituberculous subunit vaccine requires the identification and isolation of key components of the pathogen that are capable of inducing a protective immune response. Clues to identify promising subunit vaccine candidates may be found in their physicochemical and immunobiological properties. In this article, we review the evidence that the physicochemical properties of mycobacterial components can greatly impact the induction of either protective or deleterious immune response and consequently influence the potential utility as an antituberculous subunit vaccine.
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Affiliation(s)
- Suraj B Sable
- Division of TB Elimination, National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention, Mailstop G35, 1600 Clifton Road, Atlanta, GA 30333, USA
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Sable SB, Kalra M, Verma I, Khuller GK. Tuberculosis subunit vaccine design: the conflict of antigenicity and immunogenicity. Clin Immunol 2007; 122:239-51. [PMID: 17208519 DOI: 10.1016/j.clim.2006.10.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2006] [Revised: 10/12/2006] [Accepted: 10/20/2006] [Indexed: 01/02/2023]
Abstract
The attempts to find an effective antituberculous subunit vaccine are based on the assumption that it must drive a Th1 response. In the absence of effective correlates of protection, a vast array of mycobacterial components are being evaluated worldwide either on the basis of their ability to be recognized by T lymphocytes in in vitro assays during early stage of animal or human infection (antigenicity) or their capacity to induce T cell response following immunization in animal models (immunogenicity). The putative vaccine candidates selected using either of these strategies are then subjected to challenge studies in different animal models to evaluate the protective efficacy. Here we review the outcome of this current scheme of selection of vaccine candidates using an 'antigenicity' or 'immunogenicity' criterion on the actual protective efficacy observed in experimental animal models. The possible implications for the success of some of the leading vaccine candidates in clinical trials will also be discussed.
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Affiliation(s)
- Suraj B Sable
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh-160 012, India.
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22
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Benabdesselem C, Fathallah DM, Huard RC, Zhu H, Jarboui MA, Dellagi K, Ho JL, Barbouche RM. Enhanced patient serum immunoreactivity to recombinant Mycobacterium tuberculosis CFP32 produced in the yeast Pichia pastoris compared to Escherichia coli and its potential for serodiagnosis of tuberculosis. J Clin Microbiol 2006; 44:3086-93. [PMID: 16954231 PMCID: PMC1594712 DOI: 10.1128/jcm.02672-05] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
CFP32 is a Mycobacterium tuberculosis complex-restricted secreted protein that was previously reported to be present in a majority of sputum samples from patients with active tuberculosis (TB) and to stimulate serum antibody production. CFP32 (originally annotated as Rv0577 and also known as TB27.3) was therefore considered a good candidate target antigen for the rapid serodiagnosis of TB. However, the maximal sensitivity of CFP32 serorecognition may have been limited in earlier studies because recombinant CFP32 (rCFP32) produced in Escherichia coli was used as the test antibody-capture antigen, a potential shortcoming stemming from differences in bacterial protein posttranslational modifications. To further investigate the serodiagnostic potential of rCFP32 synthesized in different heterologous hosts, we expressed rCFP32 in the yeast Pichia pastoris. Compared to E. coli rCFP32, yeast rCFP32 showed a higher capacity to capture polyclonal antisera in Western blot studies. Likewise, yeast rCFP32 was significantly better recognized by the sera from TB patients and healthy Mycobacterium bovis bacillus Calmette-Guérin (BCG)-vaccinated individuals, by enzyme-linked immunosorbent assay (ELISA), than E. coli rCFP32. In subsequent testing, the yeast rCFP32-based antibody-capture ELISA had a sensitivity of 85% and a specificity of 98% for the discrimination of active TB cases (n = 40) from BCG vaccinees (n = 39). The sensitivity was surprisingly high for a single-antigen TB serodiagnostic test compared to tests using E. coli-expressed antigens. Overall, the trans-production of rCFP32 in P. pastoris significantly improved the serologic detection of CFP32-specific antibodies in patient sera, thereby offering a new, possibly better, modality for producing antigens of diagnostic potential for use in the development of immunoassays for both TB and other infectious diseases.
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Affiliation(s)
- Chaouki Benabdesselem
- Laboratory of Immunopathology, Vaccinology, and Molecular Genetics, Institut Pasteur de Tunis, Tunis, Tunisia
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23
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Grover A, Ahmed MF, Verma I, Sharma P, Khuller GK. Expression and purification of the Mycobacterium tuberculosis complex-restricted antigen CFP21 to study its immunoprophylactic potential in mouse model. Protein Expr Purif 2006; 48:274-80. [PMID: 16716602 DOI: 10.1016/j.pep.2006.03.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 03/23/2006] [Accepted: 03/24/2006] [Indexed: 10/24/2022]
Abstract
Secreted proteins encoded by different regions of difference (RDs) from the genome of Mycobacterium tuberculosis have been considered as attractive candidates for vaccination against tuberculosis owing to their absence in most BCG strains. In this study, the structural gene for the RD2 locus encoding protein CFP21 was PCR amplified and expressed as a fusion protein with hexahistidine residues in Escherichia coli. Expression of CFP21 in E. coli under transcriptional regulation of the T7 promoter yielded a protein located within inclusion bodies. The inclusion bodies were solubilized in the presence of 8M urea and the protein was purified to homogeneity under denaturing conditions at low pH using nitrilotriacetic acid (Ni-NTA) affinity chromatography. The denatured protein was renatured by gradient dialysis against a decreasing concentration of urea. The purified protein was shown to have esterase activity. CFP21 protein was evaluated for immunogenicity in C57BL/6J mice. We observed an elevated T cell proliferative response and production of IFN-gamma and IL-12 (p40). CFP21 also induced an optimum level of cytotoxic T cell activity and induced a strong humoral response as indicated by higher levels of specific IgG1 and IgG2a antibody isotypes. In addition, a moderate level of protection was observed against experimental tuberculosis. This is the first report describing esterase activity of the M. tuberculosis complex-restricted protein CFP21 and its protective potential against experimental tuberculosis.
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Affiliation(s)
- Ajay Grover
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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24
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Hill PC, Brookes RH, Adetifa IMO, Fox A, Jackson-Sillah D, Lugos MD, Donkor SA, Marshall RJ, Howie SRC, Corrah T, Jeffries DJ, Adegbola RA, McAdam KPWJ. Comparison of enzyme-linked immunospot assay and tuberculin skin test in healthy children exposed to Mycobacterium tuberculosis. Pediatrics 2006; 117:1542-8. [PMID: 16651307 DOI: 10.1542/peds.2005-2095] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE To compare the enzyme-linked immunospot (ELISPOT) assay with the tuberculin skin test (TST) in children for the diagnosis of Mycobacterium tuberculosis infection in the Gambia. METHODS We divided child contacts of sputum smear-positive tuberculosis cases into 3 age categories (<5, 5-9, and 10-14 years) and assessed agreement between the 2 tests plus their relationship to prior Bacille Calmette-Guerin (BCG) vaccination. We categorized a child's level of M tuberculosis exposure according to where he/she slept relative to a case: the same room, same house, or a different house. The relationship between exposure and test result was assessed by multiple logistic regression. RESULTS In child contacts of 287 cases, 225 (32.5%) of 693 were positive by TST and 232 (32.3%) of 718 by ELISPOT. The overall agreement between tests was 83% and the discordance was not significant. Both tests responded to the M tuberculosis exposure gradient in each age category. The percentage of those who were TST positive/ELISPOT negative increased with increasing exposure. At the lowest exposure level, the percentage of ELISPOT-positive children who were TST negative was increased compared with the highest exposure level. Neither test had evidence of false positive results because of BCG. CONCLUSIONS In Gambian children, the ELISPOT is slightly less sensitive than the TST in the diagnosis of M tuberculosis infection from recent exposure, and neither test is confounded by prior BCG vaccination. Evidence of reduced TST sensitivity in subjects with the lowest known recent M tuberculosis exposure suggests that, when maximal sensitivity is important, the 2 tests may be best used together.
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Affiliation(s)
- Philip C Hill
- Tuberculosis Division, Mulago Hospital Complex, Kampala, Uganda.
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25
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Demissie A, Leyten EMS, Abebe M, Wassie L, Aseffa A, Abate G, Fletcher H, Owiafe P, Hill PC, Brookes R, Rook G, Zumla A, Arend SM, Klein M, Ottenhoff THM, Andersen P, Doherty TM. Recognition of stage-specific mycobacterial antigens differentiates between acute and latent infections with Mycobacterium tuberculosis. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2006; 13:179-86. [PMID: 16467323 PMCID: PMC1391929 DOI: 10.1128/cvi.13.2.179-186.2006] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mycobacterium tuberculosis is estimated to infect 80 to 100 million people annually, the majority of whom do not develop clinical tuberculosis (TB) but instead maintain the infection in a latent state. These individuals generally become positive in response to a tuberculin skin test and may develop clinical TB at a later date, particularly if their immune systems are compromised. Latently infected individuals are interesting for two reasons. First, they are an important reservoir of M. tuberculosis, which needs to be considered for TB control. Second, if detected prior to recrudescence of the disease, they represent a human population that is making a protective immune response to M. tuberculosis, which is very important for defining correlates of protective immunity. In this study, we show that while responsiveness to early secretory antigenic target 6 is a good marker for M. tuberculosis infection, a strong response to the 16-kDa Rv2031c antigen (HspX or alpha-crystallin) is largely restricted to latently infected individuals, offering the possibility of differential immunodiagnosis of, or therapeutic vaccination against, TB.
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26
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Vordermeier HM, Chambers MA, Buddle BM, Pollock JM, Hewinson RG. Progress in the development of vaccines and diagnostic reagents to control tuberculosis in cattle. Vet J 2006; 171:229-44. [PMID: 16490705 DOI: 10.1016/j.tvjl.2004.11.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2004] [Indexed: 11/28/2022]
Abstract
The sharp rise of bovine tuberculosis (TB) in Great Britain and the continuing problem of wild life reservoirs in countries such as New Zealand and Great Britain have resulted in increased research efforts into the disease. Two of the goals of this research are to develop (1) cattle vaccines against TB and (2) associated diagnostic reagents that can differentiate between vaccinated and infected animals (differential diagnosis). This review summarises recent progress and describes efforts to increase the protective efficacy of the only potential TB vaccine currently available, Mycobacterium bovis BCG, and to develop specific reagents for differential diagnosis. Vaccination strategies based on DNA or protein subunit vaccination, vaccination with live viral vectors as well as heterologous prime-boost scenarios are discussed. In addition, we outline results from studies aimed at developing diagnostic reagents to allow the distinction of vaccinated from infected animals, for example antigens that are not expressed by vaccines like Mycobacterium bovis Bacille-Calmette-Guérin, but recognised strongly in Mycobacterium bovis infected cattle.
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Affiliation(s)
- H M Vordermeier
- Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
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27
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Sable SB, Kaur S, Verma I, Khuller GK. Immunodominance of low molecular weight secretory polypeptides of Mycobacterium tuberculosis to induce cytotoxic T-lymphocyte response. Vaccine 2005; 23:4947-54. [PMID: 15992971 DOI: 10.1016/j.vaccine.2005.04.046] [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: 08/25/2004] [Accepted: 04/18/2005] [Indexed: 11/23/2022]
Abstract
The cytotoxic T-lymphocyte (CTL) responses to culture filtrate antigens of Mycobacterium tuberculosis H(37)Rv (RvCFP) and purified protein derivative (PPD) were investigated in active pulmonary tuberculosis patients, healthy tuberculosis contacts and non-contacts. Healthy tuberculin skin test (Mantoux) positive tuberculosis contacts demonstrated strong CTL response against RvCFP and Mantoux reactivity was found to correlate with CTL response. The specificity of CTL response in healthy Mantoux positive contacts was further assessed using different molecular weight fractions of RvCFP. Peripheral blood mononuclear cells (PBMCs) derived CTLs recognized multiple antigenic targets and demonstrated predominant cytotoxicity against low molecular weight (below 15 kDa) protein fractions as well as those migrated in the region of 30 kDa. Subsequently, evaluation of CTL responses against selected purified prominent T-cell antigens indicated maximum CTL response directed against Ag 85 complex proteins; most notably Ag 85 A. From this study, it is suggested that identification of more mycobacterial antigens activating various CTL subsets could be an important step for the rational designing of future antituberculous vaccine.
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Affiliation(s)
- Suraj B Sable
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
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28
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Sable SB, Verma I, Khuller GK. Multicomponent antituberculous subunit vaccine based on immunodominant antigens of Mycobacterium tuberculosis. Vaccine 2005; 23:4175-84. [PMID: 15923065 DOI: 10.1016/j.vaccine.2005.03.040] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2004] [Revised: 11/12/2004] [Accepted: 03/07/2005] [Indexed: 10/25/2022]
Abstract
The low molecular mass polypeptides of secretory proteome of Mycobacterium tuberculosis are dominant targets for recognition by lymphocytes of human models of immunity to tuberculosis. In the present study, we evaluated the inherent immunogenicity of 102 individual polypeptides purified from low molecular mass region below 40kDa in mouse model of immunization. The aim of this study was to identify molecules relevant for development of subunit vaccine against tuberculosis based on high degree of immunogenecity. Here, we demonstrate that experimental multicomponent subunit vaccine (MSV) consisting of five immunodominant polypeptides with high immunogenicity (CFP-25, CFP-20.5, Ag85B, Ag85A and CPF-32) induced both cellular and humoral immune responses characterized by Th1 and Th2 cytokine induction and imparted significant protection when administered with DDA-MPL adjuvants in C57BL/6J mice. The degree of protection imparted by experimental MSV on the basis of decrease in CFU's from target organs (lungs and spleen) was comparable to BCG and total mycobacterial culture filtrate proteins (CFPs) based vaccines. These results, therefore, suggest the potential of multicomponent subunit vaccination against tuberculosis based on strongly immunogenic proteins of M. tuberculosis.
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Affiliation(s)
- Suraj B Sable
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India.
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29
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Cai H, Yu DH, Tian X, Zhu YX. Coadministration of Interleukin 2 Plasmid DNA with Combined DNA Vaccines Significantly Enhances the Protective Efficacy AgainstMycobacterium tuberculosis. DNA Cell Biol 2005; 24:605-13. [PMID: 16225391 DOI: 10.1089/dna.2005.24.605] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Coadministration of interleukin 2(IL-2) plasmid DNA with combined DNA vaccines enhanced Th1-type cellular responses by producing higher amounts of IFN-gamma with a higher ratio of antigen-specific IgG2a/IgG1. The IFN-gamma specific for Ag85B, MPT64, and MPT83 in this group was 415, 267, and 255 U/ml, respectively, and was 1.6-, 1.8-, and 2.5-fold higher than that of the same vaccine without adding IL-2. The IgG2a/IgG1 ratio for Ag85B, MPT64, and MPT83 was 4, 8, and 4, respectively, upon addition of the genetic adjuvant in the DNA vaccine, which was four times higher for every antigen when IL-2 was not included. Fluorescence activated cell sorter (FACS) analysis showed that, in the presence of IL-2, CD8+ and CD4+ T cells increased significantly, whereas in the absence of the genetic adjuvant, only a mild increase was observed for CD8+ T cells compared to the vector DNA-treated group. Bacterial CFU was reduced to less than 1/100 in the lung and to about 1/10 in the spleen relative to the same combined DNA vaccine without IL-2. The lungs of this group of mice showed much less damage due to an influx of epithelioid macrophages and less lymphocytes. RT-PCR showed that antigen genes could be detected in more organs and for a longer period of time when treated with combined DNA vaccine formulated in IL-2. We suggest that IL-2 enhanced the immunigencity and protective efficacy in immunized mice by improving the Th1-type response and also by prolonging the antigen gene expression in different organs.
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Affiliation(s)
- H Cai
- The National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing, People's Republic of China.
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30
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Doherty TM, Demissie A, Menzies D, Andersen P, Rook G, Zumla A. Effect of sample handling on analysis of cytokine responses to Mycobacterium tuberculosis in clinical samples using ELISA, ELISPOT and quantitative PCR. J Immunol Methods 2005; 298:129-41. [PMID: 15847803 DOI: 10.1016/j.jim.2005.01.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2004] [Accepted: 01/19/2005] [Indexed: 11/19/2022]
Abstract
Measuring cytokine responses to infection has proven to be invaluable for the understanding of immunity to tuberculosis in the laboratory. However, far less data are available from studies in humans and these have often produced conflicting results. Here we describe a comprehensive multi-center comparison of the most commonly used protocols for cytokine analysis: ELISA, ELISPOT and RT-PCR, in cohorts of TB patients, their household contacts and community controls. In particular, we have studied the effect on these protocols of conditions that commonly prevail in field studies, such as delays between sample collection and analysis, or different source material, such as whole blood or frozen PBMC. The results clearly show that while there is good correlation between the methods under optimal conditions, each method has strengths and weaknesses that render them more or less suitable for particular types of analyses. Researchers should carefully consider these factors when planning human field studies.
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Affiliation(s)
- T Mark Doherty
- Department of Tuberculosis Immunology, Statens Serum Institute, Copenhagen, Denmark.
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31
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Sable SB, Kumar R, Kalra M, Verma I, Khuller GK, Dobos K, Belisle JT. Peripheral blood and pleural fluid mononuclear cell responses to low-molecular-mass secretory polypeptides of Mycobacterium tuberculosis in human models of immunity to tuberculosis. Infect Immun 2005; 73:3547-58. [PMID: 15908384 PMCID: PMC1111830 DOI: 10.1128/iai.73.6.3547-3558.2005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 104 polypeptides were purified from the low-molecular-mass secretory proteome of Mycobacterium tuberculosis H(37)Rv using a combination of anion exchange column chromatography and high resolution preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by electroelution. The goal of this study was to identify polypeptides from a low-molecular-mass secretory proteome recognized by human subjects infected with M. tuberculosis and to ascertain the differences in specificity of antigen recognition by the peripheral blood mononuclear cells (PBMCs) and pleural fluid mononuclear cells (PFMCs) of these individuals. The study identified CFP-8 (Rv0496), CFP-11 (Rv2433c), CFP-14.5 (Rv2445c), and CFP-31 (Rv0831c) as novel T-cell antigens apart from previously characterized ESAT-6, TB10.4, CFP10, GroES, MTSP14, MTSP17, CFP21, MPT64, Ag85A, and Ag85B on the basis of recognition by PBMCs of tuberculosis contacts and treated tuberculosis patients. Further, polypeptides prominently recognized by PFMCs of tuberculous pleurisy patients were the same as those recognized by PBMCs of healthy contacts and treated tuberculosis patients. The results of our study indicate the homogeneity of antigenic target recognition by lymphocytes at the site of infection and at the periphery in the human subjects studied and the need to evaluate these antigenic targets as components of future antituberculous vaccines.
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Affiliation(s)
- Suraj B Sable
- Department of Biochemistry, Post-Graduate Institute of Medical Education and Research, Chandigarh, 160 012 India
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32
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McMurry J, Sbai H, Gennaro ML, Carter EJ, Martin W, De Groot AS. Analyzing Mycobacterium tuberculosis proteomes for candidate vaccine epitopes. Tuberculosis (Edinb) 2004; 85:95-105. [PMID: 15687033 DOI: 10.1016/j.tube.2004.09.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 09/27/2004] [Indexed: 11/17/2022]
Abstract
Secreted antigens of Mycobacterium tuberculosis (Mtb) induce strong T cell responses and interferon-gamma (IFN-gamma) secretion, both of which are integral in the defense against Mtb. We used web-based tools (SignaIP and Prosite) to identify putative secreted proteins from Mtb genomes CDC 1551 and H37Rv. We then used EpiMatrix, a proprietary pattern-matching algorithm, to do a preliminary analysis of these proteins for regions that contained a high number of class II MHC binding motif matches. The use of bioinformatics tools reduced the number of potential epitopes to be screened to 5% of the 1.3 million overlapping peptides. Peripheral blood mononuclear cells (PBMC) were obtained from healthy, asymptomatic tuberculin skin test-positive donors. Of the 17 highest-ranking peptide candidates that could be synthesized for this preliminary in vitro evaluation, 15 (88%) stimulated IFN-gamma response, and eight (47%) stimulated lymphocyte proliferation in vitro. IFN-gamma ELISpot assays were therefore a more sensitive test for T cell response to these peptides than were proliferation assays. One highly promiscuous epitope (MT2281-26-J, WRRRPLSSALLSFGLLLGGLPL) induced IFN-gamma secretion in PBMC from 11 of 25 Mtb immune subjects (44%). Overall, 15 epitopes, and MT2281-26-J in particular, are candidates for inclusion in a multi-epitope TB vaccine. These findings support the systematic application of bioinformatics tools to whole genomes when used in combination with in vitro methods for screening and confirming epitopes.
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Affiliation(s)
- J McMurry
- TB/HIV Research Laboratory, Brown University, Providence, RI 02912, USA
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33
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Hill PC, Fox A, Jeffries DJ, Jackson-Sillah D, Lugos MD, Owiafe PK, Donkor SA, Hammond AS, Corrah T, Adegbola RA, McAdam KPWJ, Brookes RH. Quantitative T cell assay reflects infectious load of Mycobacterium tuberculosis in an endemic case contact model. Clin Infect Dis 2004; 40:273-8. [PMID: 15655747 DOI: 10.1086/427030] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Accepted: 09/17/2004] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Currently, reliable efficacy markers for assessment of new interventions against tuberculosis (TB) are limited to disease and death. More precise measurement of the human immune response to Mycobacterium tuberculosis infection may be important. A qualitative enzyme-linked immunospot assay (ELISPOT) result for early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) offers improved specificity over the purified protein derivative (PPD) skin test reaction in the detection of M. tuberculosis infection. We evaluated the quantitative ELISPOT and PPD skin test responses to recent M. tuberculosis exposure. METHODS We studied quantitative PPD skin test and PPD ELISPOT results in 1052 healthy household contacts of index patients with cases of sputum smear-positive and culture-positive TB in The Gambia, according to a positive or negative ex vivo interferon gamma ELISPOT response to M. tuberculosis-specific antigens (ESAT-6/CFP-10). We then studied the quantitative PPD skin test and PPD ELISPOT results in patient contacts who had positive ESAT-6/CFP-10 results against a natural exposure gradient according to sleeping proximity to a patient with TB. RESULTS The number of positive results was significantly greater for both PPD skin test and PPD ELISPOT in ESAT-6/CFP-10-positive subjects, compared with others (P<.0001). However, when quantitative PPD skin test and PPD ELISPOT results were compared in ESAT-6/CFP-10-positive subjects, only the ELISPOT count was sensitive to the exposure gradient, increasing significantly according to exposure (P=.009). CONCLUSIONS The quantitative ELISPOT response to PPD in specific-antigen-positive contacts of patients with TB reflects the infectious load of M. tuberculosis as a result of recent exposure. This finding offers new possibilities for assessment of the efficacy of new interventions, and adjustment should be made for it when relating the early immune response to progression to disease.
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Affiliation(s)
- Philip C Hill
- Tuberculosis Division, Medical Research Council Laboratories, Banjul, The Gambia
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Pai M, Riley LW, Colford JM. Interferon-γ assays in the immunodiagnosis of tuberculosis: a systematic review. THE LANCET. INFECTIOUS DISEASES 2004; 4:761-76. [PMID: 15567126 DOI: 10.1016/s1473-3099(04)01206-x] [Citation(s) in RCA: 631] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A major challenge in tuberculosis control is the diagnosis and treatment of latent tuberculosis infection. Until recently, there were no alternatives to the tuberculin skin test (TST) for diagnosing latent tuberculosis. However, an alternative has now emerged in the form of a new in-vitro test: the interferon-gamma assay. We did a systematic review to assess the performance of interferon-gamma assays in the immunodiagnosis of tuberculosis. By searching databases, contacting experts and test manufacturers, we identified 75 relevant studies. The results suggest that interferon-gamma assays that use Mycobacterium tuberculosis-specific region of difference 1 (RD1) antigens (such as early secretory antigenic target 6 and culture filtrate protein 10) may have advantages over the TST, in terms of higher specificity, better correlation with exposure to M tuberculosis, and less cross-reactivity due to BCG vaccination and non-tuberculous mycobacterial infection. However, interferon-gamma assays that use RD1 antigens in isolation may maximise specificity at the cost of sensitivity. Assays that use cocktails of RD1 antigens seem to overcome this problem, and such assays have the highest accuracy. RD1-based interferon-gamma assays can potentially identify those with latent tuberculosis who are at high risk for developing active disease, but this requires confirmation. There is inadequate evidence on the value of interferon-gamma assays in the management of immunocompromised individuals, children, patients with extrapulmonary or non-tuberculous mycobacterial disease, and populations in countries where tuberculosis is endemic. Current evidence suggests that interferon-gamma assays based on cocktails of RD1 antigens have the potential to become useful diagnostic tools. Whether this potential can be realised in practice remains to be confirmed in well designed, long-term studies.
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Affiliation(s)
- Madhukar Pai
- Division of Epidemiology, School of Public Health, University of California, Berkeley, CA, USA.
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López-Vidal Y, de León-Rosales SP, Castañón-Arreola M, Rangel-Frausto MS, Meléndez-Herrada E, Sada-Díaz E. Response of IFN-gamma and IgG to ESAT-6 and 38 kDa recombinant proteins and their peptides from Mycobacterium tuberculosis in tuberculosis patients and asymptomatic household contacts may indicate possible early-stage infection in the latter. Arch Med Res 2004; 35:308-17. [PMID: 15325505 DOI: 10.1016/j.arcmed.2004.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Accepted: 04/30/2004] [Indexed: 11/20/2022]
Abstract
BACKGROUND The ESAT-6 antigen from Mycobacterium tuberculosis evokes a protective immune response in murine models and is widely recognized by tuberculosis patients (TB) and healthy household contacts (HHC). However, little is known about human immune response to this antigen in populations from areas of high endemicity. This study aimed to determine the capacity of T-cells from a group of TB patients and HHC for cell proliferation and production of cytokines type Th1 or Th2 (IL-4, IL-10, and IFN-gamma) and to identify total IgG reactivity to the recombinant protein rESAT-6 and five overlapping synthetic peptides as well as to r38 kDa and two peptides. METHODS T-cells from nine TB patients and nine HHC were stimulated with rESAT-6 and five overlapping synthetic peptides, previously selected from a set of 21 peptides and each of 16 amino acids in length (P1, P4, P6, P8, and P20). Similar experiments were carried out with r38 kDa and two peptides of 20 amino acids in length (38G and 38K). Cytokines in supernatants and total IgG from serum were determined by ELISA. RESULTS Stimulation index (SI) was highest in HHC to rESAT-6 and peptides P1, P8, and P20. Differences in response to 38 kDa and 38G peptide between TB patients and HHC were not demonstrated. Cytokines from T-cell cultures were tested with a resulting SI=3.0. IFN-gamma was produced predominantly in HHC to rESAT-6, P8, and P20, while in TB patients production of IL-10 was detected in relation to r38 kDa. IL-4 was detected in minimal amounts in both groups. IgG from TB patients was predominantly recognized in connection with rESAT-6 and the P4 peptide, with an important response against r38 kDa detected in HHC. CONCLUSIONS ESAT-6 recognition by HHC could indicate that these responses represent possible early-stage infections.
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Affiliation(s)
- Yolanda López-Vidal
- Programa de Inmunología Molecular Microbiana, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico.
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Rajavelu P, Das SD. Cell-mediated immune responses of healthy laboratory volunteers to sonicate antigens prepared from the most prevalent strains of Mycobacterium tuberculosis from South India harboring a single copy of IS6110. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2004; 10:1149-52. [PMID: 14607882 PMCID: PMC262440 DOI: 10.1128/cdli.10.6.1149-1152.2003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Our restriction fragment length polymorphism (RFLP) studies have shown that the most prevalent (40%) strains of Mycobacterium tuberculosis from South India contain a single copy of the IS6110 insertion sequence and are of importance in studying virulence and immunity. Sonicate antigens from seven such strains were used to study in vitro T-cell proliferation and gamma interferon (IFN-gamma) and interleukin-12 (IL-12) secretion as markers of protective immunity in 25 healthy subjects positive for purified protein derivative (PPD). The standard PPD and heat-killed H37Rv antigens induced the maximum levels of T-cell proliferation and IFN-gamma secretion but low levels of IL-12. All sonicate antigens induced T-cell proliferation and IFN-gamma secretion with strong positive correlation. Our results suggest that sonicate antigens from the most prevalent and recent strains of M. tuberculosis from clinical isolates have the potential to induce T-cell activation and may allow newer and specific antigens to be further characterized for diagnosis and vaccine development.
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Demissie A, Abebe M, Aseffa A, Rook G, Fletcher H, Zumla A, Weldingh K, Brock I, Andersen P, Doherty TM. Healthy individuals that control a latent infection with Mycobacterium tuberculosis express high levels of Th1 cytokines and the IL-4 antagonist IL-4delta2. THE JOURNAL OF IMMUNOLOGY 2004; 172:6938-43. [PMID: 15153513 DOI: 10.4049/jimmunol.172.11.6938] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The majority of healthy individuals exposed to Mycobacterium tuberculosis will not develop disease and identifying what constitutes "protective immunity" is one of the holy grails of M. tuberculosis immunology. It is known that IFN-gamma is essential for protection, but it is also apparent that IFN-gamma levels alone do not explain the immunity/susceptibility dichotomy. The controversy regarding correlates of immunity persists because identifying infected but healthy individuals (those who are immune) has been problematic. We have therefore used recognition of the M. tuberculosis virulence factor early secretory antigenic target 6 to identify healthy, but infected individuals from tuberculosis (TB)-endemic and nonendemic regions (Ethiopia and Denmark) and have compared signals for cytokines expressed directly ex vivo with the pattern found in TB patients. We find that TB patients are characterized by decreased levels of Th1 cytokines and increased levels of IL-10 compared with the healthy infected and noninfected community controls. Interestingly, the healthy infected subjects exhibited a selective increase of message for the IL-4 antagonist, IL-4delta2, compared with both TB patients or noninfected individuals. These data suggest that long-term control of M. tuberculosis infection is associated not just with elevated Th1 responses but also with inhibition of the Th2 response.
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38
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Hill PC, Brookes RH, Fox A, Fielding K, Jeffries DJ, Jackson-Sillah D, Lugos MD, Owiafe PK, Donkor SA, Hammond AS, Otu JK, Corrah T, Adegbola RA, McAdam KPWJ. Large-scale evaluation of enzyme-linked immunospot assay and skin test for diagnosis of Mycobacterium tuberculosis infection against a gradient of exposure in The Gambia. Clin Infect Dis 2004; 38:966-73. [PMID: 15034828 DOI: 10.1086/382362] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2003] [Accepted: 12/01/2003] [Indexed: 01/10/2023] Open
Abstract
The purified protein derivative (PPD) skin test for Mycobacterium tuberculosis infection lacks specificity. We assessed 2 more specific M. tuberculosis antigens (ESAT-6 and CFP-10) by enzyme-linked immunospot assay (ELISPOT) compared with PPD by ELISPOT and skin test in The Gambia. Of 735 household contacts of 130 sputum smear-positive tuberculosis cases, 476 (65%) tested positive by PPD ELISPOT, 300 (41%) tested positive by PPD skin test, and 218 (30%) tested positive by ESAT-6/CFP-10 ELISPOT. Only 15 (2%) had positive ESAT-6/CFP-10 results and negative PPD results by ELISPOT. With increasing M. tuberculosis exposure, the percentage of subjects who were PPD skin test positive/ESAT-6/CFP-10 ELISPOT negative increased (P<.001), whereas the percentage of subjects who were PPD skin test negative/PPD ELISPOT positive decreased (P=.011). Eighteen (31%) ESAT-6/CFP-10 ELISPOT-positive subjects in the lowest exposure category had negative PPD skin test results. ESAT-6/CFP-10 ELISPOT probably offers increased specificity in the diagnosis of M. tuberculosis infection in this tropical setting of endemicity, at the cost of some sensitivity.
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Affiliation(s)
- Philip C Hill
- Tuberculosis Division, Medical Research Council Laboratories, Banjul, The Gambia.
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Huard RC, Chitale S, Leung M, Lazzarini LCO, Zhu H, Shashkina E, Laal S, Conde MB, Kritski AL, Belisle JT, Kreiswirth BN, Lapa e Silva JR, Ho JL. The Mycobacterium tuberculosis complex-restricted gene cfp32 encodes an expressed protein that is detectable in tuberculosis patients and is positively correlated with pulmonary interleukin-10. Infect Immun 2004; 71:6871-83. [PMID: 14638775 PMCID: PMC308900 DOI: 10.1128/iai.71.12.6871-6883.2003] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human tuberculosis (TB) is caused by the bacillus Mycobacterium tuberculosis, a subspecies of the M. tuberculosis complex (MTC) of mycobacteria. Postgenomic dissection of the M. tuberculosis proteome is ongoing and critical to furthering our understanding of factors mediating M. tuberculosis pathobiology. Towards this end, a 32-kDa putative glyoxalase in the culture filtrate (CF) of growing M. tuberculosis (originally annotated as Rv0577 and hereafter designated CFP32) was identified, cloned, and characterized. The cfp32 gene is MTC restricted, and the gene product is expressed ex vivo as determined by the respective Southern and Western blot testing of an assortment of mycobacteria. Moreover, the cfp32 gene sequence is conserved within the MTC, as no polymorphisms were found in the tested cfp32 PCR products upon sequence analysis. Western blotting of M. tuberculosis subcellular fractions localized CFP32 predominantly to the CF and cytosolic compartments. Data to support the in vivo expression of CFP32 were provided by the serum recognition of recombinant CFP32 in 32% of TB patients by enzyme-linked immunosorbent assay (ELISA) as well as the direct detection of CFP32 by ELISA in the induced sputum samples from 56% of pulmonary TB patients. Of greatest interest was the observation that, per sample, sputum CFP32 levels (a potential indicator of increasing bacterial burden) correlated with levels of expression in sputum of interleukin-10 (an immunosuppressive cytokine and a putative contributing factor to disease progression) but not levels of gamma interferon (a key cytokine in the protective immune response in TB), as measured by ELISA. Combined, these data suggest that CFP32 serves a necessary biological function(s) in tubercle bacilli and may contribute to the M. tuberculosis pathogenic mechanism. Overall, CFP32 is an attractive target for drug and vaccine design as well as new diagnostic strategies.
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Affiliation(s)
- Richard C Huard
- Division of International Medicine and Infectious Diseases, Department of Medicine, Joan and Sanford I. Weill Medical College, Cornell University, New York, NY 10021, USA
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40
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Al-Attiyah R, Mustafa AS, Abal AT, Madi NM, Andersen P. Restoration of mycobacterial antigen-induced proliferation and interferon-γ responses in peripheral blood mononuclear cells of tuberculosis patients upon effective chemotherapy. ACTA ACUST UNITED AC 2003; 38:249-56. [PMID: 14522460 DOI: 10.1016/s0928-8244(03)00166-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Peripheral blood mononuclear cells (PBMC) were obtained from culture-proven tuberculosis (TB) patients before and after 2 and 6 months of chemotherapy with a multi-drug regimen. PBMC were tested for cellular responses in antigen-induced proliferation and interferon-gamma (IFN-gamma) assays in response to complex mycobacterial antigens (whole cell Mycobacterium bovis BCG and M. tuberculosis, cell walls and short-term culture filtrate [ST-CF] of M. tuberculosis), fractionated ST-CF antigens (fractions F1-F10) and ESAT-6. The responses in TB patients before anti-TB treatment were low (median stimulation index (SI)=1-7, median delta IFN-gamma=0-12 U ml(-1), and percent responders=13-67%) to all the antigenic preparations. Following the administration of anti-TB chemotherapy for 2 months, there were significant (P<0.05) improvements in the cellular responses (median SI=9-76, median delta IFN-gamma=3-70 U ml(-1), and percent responders=33-100%) to most of the antigenic preparations tested. However, concanavalin A-induced proliferation responses of PBMC from the same patients before and after 2 months of chemotherapy were high and comparable (median SI=101 and 114, respectively, P>0.05, 100% responders). A further increase in IFN-gamma responses (median delta IFN-gamma=14-250 U ml(-1) and percent responders=43-100%) to mycobacterial antigens was observed in patients receiving chemotherapy for 6 months. Among the ST-CF fractions, F1 and F2 containing low molecular mass proteins resulted in the highest responses, whereas ESAT-6 showed responses comparable to these fractions only in a minority of the patients. HLA-DR typing of these patients showed heterogeneity in the expression of molecules encoded by HLA-DRB genes. These results show that effective chemotherapy restores cellular responses of TB patients to a large number of M. tuberculosis antigens, which could be useful in monitoring the efficacy of anti-TB treatment.
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Affiliation(s)
- R Al-Attiyah
- Department of Microbiology, Faculty of Medicine, Kuwait University, PO Box 24923, 13110 Safat, Kuwait.
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41
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Subronto YW, van Meijgaarden KE, Geluk A, Arend SM, Sunardi T, Franken KLMC, Hisyam B, de Vries RRP, Ottenhoff THM. Interferon-gamma production in response to M. tuberculosis antigens in TB patients in Indonesia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 531:249-60. [PMID: 12916797 DOI: 10.1007/978-1-4615-0059-9_21] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Affiliation(s)
- Yanri W Subronto
- Dept. of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands.
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Abstract
Years of intense research aimed at developing a new and improved vaccine against tuberculosis (TB) are now moving from the laboratories and into the field. Many groups have provided strong evidence for the potential of novel vaccines using a variety of different strategies and the most promising are just beginning to enter human safety trials. As research has developed over the years, the complexity of the TB situation at the global level and its influence on vaccine development strategies has become more and more clear. From being mainly focused on the development of a vaccine that could be given at birth and provide lifelong protection, it is now clear that the current goal may need to be a vaccine to be given to a population where the majority is already sensitized either by previous infection, exposure to other mycobacteria or by Bacille Calmette-Guerin vaccination. With the increasing awareness of the different immune mechanisms operating under those circumstances, such a vaccine still represents a significant challenge for immunologists and microbiologists working in this field.
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Affiliation(s)
- Anja W Olsen
- Department of Infectious Disease Immunology, Statens Serum Institute, Artillerivej 5, 2300 Copenhagen S, Denmark
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43
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Vordermeier HM, Chambers MA, Cockle PJ, Whelan AO, Simmons J, Hewinson RG. Correlation of ESAT-6-specific gamma interferon production with pathology in cattle following Mycobacterium bovis BCG vaccination against experimental bovine tuberculosis. Infect Immun 2002; 70:3026-32. [PMID: 12010994 PMCID: PMC128013 DOI: 10.1128/iai.70.6.3026-3032.2002] [Citation(s) in RCA: 282] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vaccine development and the understanding of the pathology of bovine tuberculosis in cattle would be greatly facilitated by the definition of immunological correlates of protection and/or pathology. To address these questions, cattle were vaccinated with Mycobacterium bovis bacillus Calmette-Guérin (BCG) and were then challenged with virulent M. bovis. Applying a semiquantitative pathology-scoring system, we were able to demonstrate that BCG vaccination imparted significant protection by reducing the disease severity on average by 75%. Analysis of cellular immune responses following M. bovis challenge demonstrated that proliferative T-cell and gamma interferon (IFN-gamma) responses towards the M. bovis-specific antigen ESAT-6, whose gene is absent from BCG, were generally low in vaccinated animals but were high in all nonvaccinated calves. Importantly, the amount of ESAT-6-specific IFN-gamma measured by enzyme-linked immunosorbent assay after M. bovis challenge, but not the frequency of responding cells, correlated positively with the degree of pathology found 18 weeks after infection. Diagnostic reagents based on antigens not present in BCG, like ESAT-6 and CFP-10, were still able to distinguish BCG-vaccinated, diseased animals from BCG-vaccinated animals without signs of disease. In summary, our results suggest that the determination of ESAT-6-specific IFN-gamma, while not a direct correlate of protection, constitutes nevertheless a useful prognostic immunological marker predicting both vaccine efficacy and disease severity.
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Affiliation(s)
- H Martin Vordermeier
- Veterinary Laboratories Agency Weybridge, TB Research Group, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom.
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Wedlock DN, Keen DL, McCarthy AR, Andersen P, Buddle BM. Effect of different adjuvants on the immune responses of cattle vaccinated with Mycobacterium tuberculosis culture filtrate proteins. Vet Immunol Immunopathol 2002; 86:79-88. [PMID: 11943331 DOI: 10.1016/s0165-2427(02)00017-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The development of improved vaccines for bovine tuberculosis is urgently required as a cost effective solution for control and eventual eradication of tuberculosis in domestic animals. Studies in small animal models of tuberculosis have shown that vaccination with culture filtrate proteins (CFP), prepared from Mycobacterium tuberculosis or M. bovis, can induce cellular immune responses and confer a level of protection against aerogenic challenge with virulent mycobacteria. As a first step in the development of a mycobacterial CFP vaccine for protection of cattle against bovine tuberculosis, the immune responses of cattle vaccinated with short-term culture filtrate proteins (ST-CFP) from M. tuberculosis and formulated with different adjuvants were compared with those vaccinated with bacille Calmette-Guerin (BCG). The adjuvants included dimethyldioctyldecyl ammonium bromide (DDA), diethylaminoethyl (DEAE)-dextran, and ST-CFP adsorbed onto polystyrene beads. Vaccination with ST-CFP/DEAE-dextran induced high levels of interleukin-2 (IL-2) but low levels of interferon-gamma (IFN-gamma) from whole-blood cultures stimulated with M. tuberculosis ST-CFP in comparison with the strong IFN-gamma and IL-2 responses induced after vaccination with BCG. ST-CFP/DEAE-dextran also induced a strong antigen-specific immunoglobulin antibody response with both immunoglobulin G1 (IgG1) and IgG2 isotypes. Vaccination with ST-CFP/beads induced a weak IgG1-biased antibody response but no IFN-gamma or IL-2 response. DDA did not induce significant immune responses in animals vaccinated with ST-CFP. In comparison to the moderate delayed-type hypersensitivity (DTH) responses induced by vaccination with subcutaneous BCG, none of the ST-CFP vaccines induced a significant DTH response to either M. tuberculosis ST-CFP or bovine purified protein derivative (PPD). While the ST-CFP vaccines used in this study have not induced strong antigen-specific cellular immune responses in cattle comparable to those induced by BCG, they are immunogenic in cattle and it may be possible to overcome this problem by using adjuvants that more effectively promote IFN-gamma responses in this species.
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Affiliation(s)
- D N Wedlock
- AgResearch Ltd., Wallaceville Animal Research Centre, P.O. Box 40063, Upper Hutt, New Zealand.
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45
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Doherty TM, Demissie A, Olobo J, Wolday D, Britton S, Eguale T, Ravn P, Andersen P. Immune responses to the Mycobacterium tuberculosis-specific antigen ESAT-6 signal subclinical infection among contacts of tuberculosis patients. J Clin Microbiol 2002; 40:704-6. [PMID: 11826002 PMCID: PMC153355 DOI: 10.1128/jcm.40.2.704-706.2002] [Citation(s) in RCA: 194] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Diagnosis of latent Mycobacterium tuberculosis infection is considered essential for tuberculosis control but is hampered by the lack of specific reagents. We report that strong recognition of tuberculosis complex-specific antigen ESAT-6 by healthy household contacts of tuberculosis patients correlates with the subsequent development of active tuberculosis during a 2-year follow-up period.
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Affiliation(s)
- T Mark Doherty
- Department of Tuberculosis Immunology, Statens Serum Institute. Hvidovre Hospital, Copenhagen, Denmark.
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46
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Cappelli G, Volpe P, Sanduzzi A, Sacchi A, Colizzi V, Mariani F. Human macrophage gamma interferon decreases gene expression but not replication of Mycobacterium tuberculosis: analysis of the host-pathogen reciprocal influence on transcription in a comparison of strains H37Rv and CMT97. Infect Immun 2001; 69:7262-70. [PMID: 11705896 PMCID: PMC98810 DOI: 10.1128/iai.69.12.7262-7270.2001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2001] [Accepted: 08/15/2001] [Indexed: 12/18/2022] Open
Abstract
Mycobacterium tuberculosis is an intracellular pathogen that readily survives and replicates in human macrophages (MPhi). Host cells have developed different mycobactericidal mechanisms, including the production of inflammatory cytokines. The aim of this study was to compare the MPhi response, in terms of cytokine gene expression, to infection with the M. tuberculosis laboratory strain H37Rv and the clinical M. tuberculosis isolate CMT97. Both strains induce the production of interleukin-12 (IL-12) and IL-16 at comparable levels. However, the clinical isolate induces a significantly higher and more prolonged MPhi activation, as shown by reverse transcription-PCR analysis of IL-1beta, IL-6, IL-10, transforming growth factor beta, tumor necrosis factor alpha, and gamma interferon (IFN-gamma) transcripts. Interestingly, when IFN-gamma transcription is high, the number of M. tuberculosis genes expressed decreases and vice versa, whereas no mycobactericidal effect was observed in terms of bacterial growth. Expression of 11 genes was also studied in the two M. tuberculosis strains by infecting resting or activated MPhi and compared to bacterial intracellular survival. In both cases, a peculiar inverse correlation between expression of these genes and multiplication was observed. The number and type of genes expressed by the two strains differed significantly.
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Affiliation(s)
- G Cappelli
- Institute of Neurobiology and Molecular Medicine, National Research Council, Rome, Italy
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Vekemans J, Lienhardt C, Sillah JS, Wheeler JG, Lahai GP, Doherty MT, Corrah T, Andersen P, McAdam KP, Marchant A. Tuberculosis contacts but not patients have higher gamma interferon responses to ESAT-6 than do community controls in The Gambia. Infect Immun 2001; 69:6554-7. [PMID: 11553606 PMCID: PMC98797 DOI: 10.1128/iai.69.10.6554-6557.2001] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Mycobacterium tuberculosis antigen ESAT-6 has been proposed for tuberculosis immunodiagnosis. In The Gambia, 30% of community controls produced gamma interferon (IFN-gamma) in response to ESAT-6. Increased proportions of responders and intensities of responses were found in household contacts. Responses that were initially low in tuberculosis patients increased after treatment. An ESAT-6 IFN-gamma assay will be of limited use in the diagnosis of tuberculosis in countries where tuberculosis is endemic. Its role in contact tracing should be evaluated further.
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MESH Headings
- Adolescent
- Adult
- Antigens, Bacterial/immunology
- Antigens, Bacterial/pharmacology
- Bacterial Proteins
- Biomarkers
- Cells, Cultured
- Community-Acquired Infections/immunology
- Endemic Diseases
- Female
- Gambia/epidemiology
- Humans
- Interferon-gamma/blood
- Leukocytes, Mononuclear/cytology
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/immunology
- Male
- Middle Aged
- Mycobacterium tuberculosis/immunology
- Prospective Studies
- Tuberculin Test
- Tuberculosis, Pulmonary/blood
- Tuberculosis, Pulmonary/epidemiology
- Tuberculosis, Pulmonary/immunology
- Tuberculosis, Pulmonary/transmission
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Affiliation(s)
- J Vekemans
- Medical Research Council Laboratories, Fajara, The Gambia.
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48
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Abstract
Protection of cattle against bovine tuberculosis by vaccination could be an important control strategy in countries where there is persistence of Mycobacterium bovis infection in wildlife and in developing countries where it is not economical to implement a 'test and slaughter' control programme. Early field trials with Bacille Calmette Guerin (BCG) M. bovis vaccine in cattle produced disappointing results, with induction of tuberculin skin-test reactivity following vaccination and low levels of protection. However, recent studies using a low dose of BCG vaccine in cattle have produced more encouraging results and field trials should now be carried out in developing countries to determine whether this low dose BCG vaccination strategy will reduce the spread of infection. The options for new candidate tuberculosis vaccines have increased markedly in the last decade with the advent of new attenuated strains of M. bovis, and sub-unit protein and recombinant DNA vaccines. Some of these new types of vaccines have recently been tested in cattle. New attenuated M. bovis vaccines induced greater protection than BCG vaccine in cattle which had been sensitized to environmental mycobacteria prior to vaccination. In contrast, it has proved difficult to stimulate appropriate immune responses in cattle necessary for protection with sub-unit protein and recombinant DNA vaccines and better immunological adjuvants are required for these types of vaccines. Progress in the development of new tuberculosis vaccines has been very rapid in the past decade and the prospects for vaccination to control and eradicate bovine tuberculosis are encouraging.
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Affiliation(s)
- B M Buddle
- AgResearch, Wallaceville Animal Research Centre, Upper Hutt, New Zealand.
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49
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Wedlock DN, Vesosky B, Skinner MA, de Lisle GW, Orme IM, Buddle BM. Vaccination of cattle with Mycobacterium bovis culture filtrate proteins and interleukin-2 for protection against bovine tuberculosis. Infect Immun 2000; 68:5809-15. [PMID: 10992489 PMCID: PMC101541 DOI: 10.1128/iai.68.10.5809-5815.2000] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this study vaccines prepared from culture filtrate proteins (CFP) of Mycobacterium bovis and interleukin-2 (IL-2) were tested in cattle for their capacity to stimulate immune responses and to protect against an intratracheal challenge with virulent M. bovis. Nine groups of cattle were vaccinated with combinations of different doses of CFP and bovine IL-2 mixed with a monophosphoryl lipid A (MPL) adjuvant. An additional group was vaccinated with M. bovis BCG. Immune responses in b1P-IL-2-vaccinated animals differed from those seen in BCG-vaccinated animals by inducing high antigen-specific antibody responses and low levels of gamma interferon and IL-2 released from purified protein derivative-stimulated whole-blood cultures. In a concurrent experiment, additional animals were added to the high-dose CFP-IL-2, MPL control, and BCG groups and these expanded groups of animals were challenged intratracheally with virulent M. bovis. Although the lung lesion scores were significantly lower for both the CFP-IL-2-and BCG-vaccinated groups compared to the MPL control group, the overall level of protection was greatest for the BCG-vaccinated animals. There were more animals with extrathoracic spread of disease in the CFP-IL-2 group than in the other groups. While vaccination of cattle with M. bovis CFP gave an encouraging reduction in tuberculous lesions and did not induce a delayed-type hypersensitivity response to PPD, future CFP vaccines must prevent any extrathoracic spread of disease.
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Affiliation(s)
- D N Wedlock
- AgResearch, Wallaceville Animal Research Centre, Upper Hutt, New Zealand.
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50
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Schwander SK, Torres M, Carranza C C, Escobedo D, Tary-Lehmann M, Anderson P, Toossi Z, Ellner JJ, Rich EA, Sada E. Pulmonary mononuclear cell responses to antigens of Mycobacterium tuberculosis in healthy household contacts of patients with active tuberculosis and healthy controls from the community. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:1479-85. [PMID: 10903753 DOI: 10.4049/jimmunol.165.3.1479] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Protective immunity against Mycobacterium tuberculosis requires CD4+ lymphocyte-mediated immune responses and IFN-gamma activity. As the primary portal of entry of M. tuberculosis is the lung, pulmonary immune responses against multiple M. tuberculosis Ags were compared between both M. tuberculosis-exposed tuberculin skin test-positive healthy household contacts (HHC) of patients with active sputum smear and culture-positive tuberculosis and tuberculin skin test-positive healthy control individuals from the community (CC). Frequencies of M. tuberculosis Ag-specific IFN-gamma-producing cells, IFN-gamma concentrations in culture supernatants, and DNA synthesis in bronchoalveolar cells (BAC) and PBMC were studied in HHC (n = 10) and CC (n = 15). Using enzyme-linked immunospot assay we found higher frequencies of IFN-gamma-producing cells with specificity to M. tuberculosis-secreted Ag 85 (Ag 85) in BAC from HHC than in BAC from CC (p < 0.022) and relative to autologous PBMC, indicating compartmentalization of Ag 85-specific cells to the lungs. Further, IFN-gamma-producing cells with specificity to components A and B of Ag 85 were specifically compartmentalized to the lungs in HHC (p < 0. 05). IFN-gamma concentrations in culture supernatants of BAC and Ag-specific DNA synthesis were low and comparable in the two subject groups. Increased immune responses to Ag 85 at the site of repeated exposure to M. tuberculosis (the lung) may represent an important component of protective immunity against M. tuberculosis. Correlates of protective immunity against M. tuberculosis are required for assessment of the efficiency of anti-tuberculous vaccines.
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Affiliation(s)
- S K Schwander
- Department of Medicine, Case Western Reserve University and University Hospitals of Cleveland, Cleveland, OH 44106, USA
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