1
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Szachniewicz MM, van den Eeden SJF, van Meijgaarden KE, Franken KLMC, van Veen S, Geluk A, Bouwstra JA, Ottenhoff THM. Cationic pH-sensitive liposome-based subunit tuberculosis vaccine induces protection in mice challenged with Mycobacterium tuberculosis. Eur J Pharm Biopharm 2024:114437. [PMID: 39122053 DOI: 10.1016/j.ejpb.2024.114437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 07/18/2024] [Accepted: 08/05/2024] [Indexed: 08/12/2024]
Abstract
Tuberculosis (TB) has been and still is a global emergency for centuries. Prevention of disease through vaccination would have a major impact on disease prevalence, but the only available current vaccine, BCG, has insufficient impact. In this article, a novel subunit vaccine against TB was developed, using the Ag85B-ESAT6-Rv2034 fusion antigen, two adjuvants - CpG and MPLA, and a cationic pH-sensitive liposome as a delivery system, representing a new TB vaccine delivery strategy not previously reported for TB. In vitro in human dendritic cells (DCs), the adjuvanted formulation induced a significant increase in the production of (innate) cytokines and chemokines compared to the liposome without additional adjuvants. In vivo, the new vaccine administrated subcutaneously significantly reduced Mycobacterium tuberculosis (Mtb) bacterial load in the lungs and spleens of mice, significantly outperforming results from mice vaccinated with the antigen mixed with adjuvants without liposomes. In-depth analysis underpinned the vaccine's effectiveness in terms of its capacity to induce polyfunctional CD4+ and CD8+ T-cell responses, both considered essential for controlling Mtb infection. Also noteworthy was the differential abundance of various CD69+ B-cell subpopulations, which included IL17-A-producing B cells. The vaccine stimulated robust antigen-specific antibody titers, further extending its potential as a novel protective agent against TB.
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Affiliation(s)
- M M Szachniewicz
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands.
| | - S J F van den Eeden
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands
| | - K E van Meijgaarden
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands
| | - K L M C Franken
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands
| | - S van Veen
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands
| | - A Geluk
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands
| | - J A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, The Netherlands
| | - T H M Ottenhoff
- Department of Infectious Diseases, Leiden University Medical Center (LUMC), The Netherlands
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2
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Kayongo A, Nyiro B, Siddharthan T, Kirenga B, Checkley W, Lutaakome Joloba M, Ellner J, Salgame P. Mechanisms of lung damage in tuberculosis: implications for chronic obstructive pulmonary disease. Front Cell Infect Microbiol 2023; 13:1146571. [PMID: 37415827 PMCID: PMC10320222 DOI: 10.3389/fcimb.2023.1146571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 06/05/2023] [Indexed: 07/08/2023] Open
Abstract
Pulmonary tuberculosis is increasingly recognized as a risk factor for COPD. Severe lung function impairment has been reported in post-TB patients. Despite increasing evidence to support the association between TB and COPD, only a few studies describe the immunological basis of COPD among TB patients following successful treatment completion. In this review, we draw on well-elaborated Mycobacterium tuberculosis-induced immune mechanisms in the lungs to highlight shared mechanisms for COPD pathogenesis in the setting of tuberculosis disease. We further examine how such mechanisms could be exploited to guide COPD therapeutics.
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Affiliation(s)
- Alex Kayongo
- Department of Medicine, Center for Emerging Pathogens, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
- Department of Immunology and Molecular Biology, College of Health Sciences, Makerere University, Kampala, Uganda
- Makerere University College of Health Sciences, Lung Institute, Makerere University, Kampala, Uganda
| | - Brian Nyiro
- Department of Medicine, Center for Emerging Pathogens, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
- Department of Immunology and Molecular Biology, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Trishul Siddharthan
- Division of Pulmonary and Critical Care Medicine, University of Miami, Miami, FL, United States
| | - Bruce Kirenga
- Makerere University College of Health Sciences, Lung Institute, Makerere University, Kampala, Uganda
| | - William Checkley
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
- Center for Global Non-Communicable Disease Research and Training, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Moses Lutaakome Joloba
- Makerere University College of Health Sciences, Lung Institute, Makerere University, Kampala, Uganda
| | - Jerrold Ellner
- Department of Medicine, Center for Emerging Pathogens, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
| | - Padmini Salgame
- Department of Medicine, Center for Emerging Pathogens, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
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3
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Hunter RL. The Pathogenesis of Tuberculosis-The Koch Phenomenon Reinstated. Pathogens 2020; 9:E813. [PMID: 33020397 PMCID: PMC7601602 DOI: 10.3390/pathogens9100813] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/11/2020] [Accepted: 09/19/2020] [Indexed: 12/24/2022] Open
Abstract
Research on the pathogenesis of tuberculosis (TB) has been hamstrung for half a century by the paradigm that granulomas are the hallmark of active disease. Human TB, in fact, produces two types of granulomas, neither of which is involved in the development of adult type or post-primary TB. This disease begins as the early lesion; a prolonged subclinical stockpiling of secreted mycobacterial antigens in foamy alveolar macrophages and nearby highly sensitized T cells in preparation for a massive necrotizing hypersensitivity reaction, the Koch Phenomenon, that produces caseous pneumonia that is either coughed out to form cavities or retained to become the focus of post-primary granulomas and fibrocaseous disease. Post-primary TB progresses if the antigens are continuously released and regresses when they are depleted. This revised paradigm is supported by nearly 200 years of research and suggests new approaches and animal models to investigate long standing mysteries of human TB and vaccines that inhibit the early lesion to finally end its transmission.
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Affiliation(s)
- Robert L Hunter
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center at Houston, Houston, TX 77030, USA
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4
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Aagaard C, Knudsen NPH, Sohn I, Izzo AA, Kim H, Kristiansen EH, Lindenstrøm T, Agger EM, Rasmussen M, Shin SJ, Rosenkrands I, Andersen P, Mortensen R. Immunization with Mycobacterium tuberculosis-Specific Antigens Bypasses T Cell Differentiation from Prior Bacillus Calmette-Guérin Vaccination and Improves Protection in Mice. THE JOURNAL OF IMMUNOLOGY 2020; 205:2146-2155. [PMID: 32887748 DOI: 10.4049/jimmunol.2000563] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/05/2020] [Indexed: 01/03/2023]
Abstract
Despite the fact that the majority of people in tuberculosis (TB)-endemic areas are vaccinated with the Bacillus Calmette-Guérin (BCG) vaccine, TB remains the leading infectious cause of death. Data from both animal models and humans show that BCG and subunit vaccines induce T cells of different phenotypes, and little is known about how BCG priming influences subsequent booster vaccines. To test this, we designed a novel Mycobacterium tuberculosis-specific (or "non-BCG") subunit vaccine with protective efficacy in both mice and guinea pigs and compared it to a known BCG boosting vaccine. In naive mice, this M. tuberculosis-specific vaccine induced similar protection compared with the BCG boosting vaccine. However, in BCG-primed animals, only the M. tuberculosis-specific vaccine added significantly to the BCG-induced protection. This correlated with the priming of T cells with a lower degree of differentiation and improved lung-homing capacity. These results have implications for TB vaccine design.
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Affiliation(s)
- Claus Aagaard
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Niels Peter Hell Knudsen
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Iben Sohn
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Angelo A Izzo
- Colorado State University, Department of Microbiology, Immunology and Pathology, Fort Collins, CO 80523
| | - Hongmin Kim
- Department of Microbiology, Institute for Immunology and Immunological Diseases, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, South Korea
| | - Emma Holsey Kristiansen
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Thomas Lindenstrøm
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Else Marie Agger
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Michael Rasmussen
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut, DK-2300 Copenhagen, Denmark; and
| | - Sung Jae Shin
- Department of Microbiology, Institute for Immunology and Immunological Diseases, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, South Korea
| | - Ida Rosenkrands
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Peter Andersen
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark.,Department of Immunology and Microbiology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Rasmus Mortensen
- Department of Infectious Disease Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark;
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5
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Afkhami S, Lai R, D'agostino MR, Vaseghi-Shanjani M, Zganiacz A, Yao Y, Jeyanathan M, Xing Z. Single-Dose Mucosal Immunotherapy With Chimpanzee Adenovirus-Based Vaccine Accelerates Tuberculosis Disease Control and Limits Its Rebound After Antibiotic Cessation. J Infect Dis 2020; 220:1355-1366. [PMID: 31198944 DOI: 10.1093/infdis/jiz306] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/12/2019] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The development of strategies to accelerate disease resolution and shorten antibiotic therapy is imperative in curbing the global tuberculosis epidemic. Therapeutic application of novel vaccines adjunct to antibiotics represents such a strategy. METHODS By using a murine model of pulmonary tuberculosis (TB), we have investigated whether a single respiratory mucosal therapeutic delivery of a novel chimpanzee adenovirus-vectored vaccine expressing Ag85A (AdCh68Ag85A) accelerates TB disease control in conjunction with antibiotics and restricts pulmonary disease rebound after premature (nonsterilizing) antibiotic cessation. RESULTS We find that immunotherapy via the respiratory mucosal, but not parenteral, route significantly accelerates pulmonary mycobacterial clearance, limits lung pathology, and restricts disease rebound after premature antibiotic cessation. We further show that vaccine-activated antigen-specific T cells, particularly CD8 T cells, in the lung play an important role in immunotherapeutic effects. CONCLUSIONS Our results indicate that a single-dose respiratory mucosal immunotherapy with AdCh68Ag85A adjunct to antibiotic therapy has the potential to significantly accelerate disease control and shorten the duration of conventional treatment. Our study provides the proof of principle to support therapeutic applications of viral-vectored vaccines via the respiratory route.
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Affiliation(s)
- Sam Afkhami
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Rocky Lai
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Michael R D'agostino
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Maryam Vaseghi-Shanjani
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Anna Zganiacz
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Yushi Yao
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Mangalakumari Jeyanathan
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Zhou Xing
- McMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
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6
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Ravimohan S, Kornfeld H, Weissman D, Bisson GP. Tuberculosis and lung damage: from epidemiology to pathophysiology. Eur Respir Rev 2018; 27:27/147/170077. [PMID: 29491034 PMCID: PMC6019552 DOI: 10.1183/16000617.0077-2017] [Citation(s) in RCA: 222] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/28/2017] [Indexed: 12/12/2022] Open
Abstract
A past history of pulmonary tuberculosis (TB) is a risk factor for long-term respiratory impairment. Post-TB lung dysfunction often goes unrecognised, despite its relatively high prevalence and its association with reduced quality of life. Importantly, specific host and pathogen factors causing lung impairment remain unclear. Host immune responses probably play a dominant role in lung damage, as excessive inflammation and elevated expression of lung matrix-degrading proteases are common during TB. Variability in host genes that modulate these immune responses may determine the severity of lung impairment, but this hypothesis remains largely untested. In this review, we provide an overview of the epidemiological literature on post-TB lung impairment and link it to data on the pathogenesis of lung injury from the perspective of dysregulated immune responses and immunogenetics. Host factors driving lung injury in TB likely contribute to variable patterns of pulmonary impairment after TBhttp://ow.ly/a3of30hBsxB
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Affiliation(s)
- Shruthi Ravimohan
- Dept of Medicine, Division of Infectious Diseases, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Hardy Kornfeld
- Dept of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Drew Weissman
- Dept of Medicine, Division of Infectious Diseases, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Gregory P Bisson
- Dept of Medicine, Division of Infectious Diseases, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.,Dept of Biostatistics and Epidemiology, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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7
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Billeskov R, Lindenstrøm T, Woodworth J, Vilaplana C, Cardona PJ, Cassidy JP, Mortensen R, Agger EM, Andersen P. High Antigen Dose Is Detrimental to Post-Exposure Vaccine Protection against Tuberculosis. Front Immunol 2018; 8:1973. [PMID: 29379507 PMCID: PMC5775287 DOI: 10.3389/fimmu.2017.01973] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 12/20/2017] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb), the etiologic agent of tuberculosis (TB), causes 1.8M deaths annually. The current vaccine, BCG, has failed to eradicate TB leaving 25% of the world’s population with latent Mtb infection (LTBI), and 5–10% of these people will reactivate and develop active TB. An efficient therapeutic vaccine targeting LTBI could have an enormous impact on global TB incidence, and could be an important aid in fighting multidrug resistance, which is increasing globally. Here we show in a mouse model using the H56 (Ag85B-ESAT-6-Rv2660) TB vaccine candidate that post-exposure, but not preventive, vaccine protection requires low vaccine antigen doses for optimal protection. Loss of protection from high dose post-exposure vaccination was not associated with a loss of overall vaccine response magnitude, but rather with greater differentiation and lower functional avidity of vaccine-specific CD4 T cells. High vaccine antigen dose also led to a decreased ability of vaccine-specific CD4 T cells to home into the Mtb-infected lung parenchyma, a recently discovered important feature of T cell protection in mice. These results underscore the importance of T cell quality rather than magnitude in TB-vaccine protection, and the significant role that antigen dosing plays in vaccine-mediated protection.
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Affiliation(s)
- Rolf Billeskov
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Thomas Lindenstrøm
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Joshua Woodworth
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Cristina Vilaplana
- Unitat de Tuberculosi Experimental, Institut per a la Investigació en Ciències de la Salut Germans Trias I Pujol, CIBER Enfermedades Respiratorias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Spain
| | - Pere-Joan Cardona
- Unitat de Tuberculosi Experimental, Institut per a la Investigació en Ciències de la Salut Germans Trias I Pujol, CIBER Enfermedades Respiratorias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Spain
| | - Joseph P Cassidy
- Veterinary Sciences Centre, School of Veterinary Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - Rasmus Mortensen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Else Marie Agger
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Peter Andersen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
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8
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Lima D, ZÁrate-Bladés C, Souza P, Trombone A, Santos-Junior R, Brandão L, Masson A, Bonato V, Coelho-Castelo A, Sartori A, Vendramini M, Soares E, Benvenutti L, Silva C, Coelho V. No Evidence of Pathological Autoimmunity following Mycobacterium Leprae Heat-Shock Protein 65-Dna Vaccination in Mice. EUR J INFLAMM 2017. [DOI: 10.1177/1721727x0900700204] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Heat-shock proteins (HSPs) are currently one of the most promising targets for the development of immunotherapy against tumours and autoimmune disorders. This protein family has the capacity to activate or modulate the function of different immune system cells. They induce the activation of monocytes, macrophages and dendritic cells, and contribute to cross-priming, an important mechanism of presentation of exogenous antigen in the context of MHC class I molecules. These various immunological properties of HSP have encouraged their use in several clinical trials. Nevertheless, an important issue regarding these proteins is whether the high homology among HSPs across different species may trigger the breakdown of immune tolerance and induce autoimmune diseases. We have developed a DNA vaccine codifying the Mycobacterium leprae Hsp65 (DNAhsp65), which showed to be highly immunogenic and protective against experimental tuberculosis. Here, we address the question of whether DNAhsp65 immunization could induce pathological autoimmunity in mice. Our results show that DNAhsp65 vaccination induced antibodies that can recognize the human Hsp60 but did not induce harmful effects in 16 different organs analysed by histopathology up to 210 days after vaccination. We also showed that anti-DNA antibodies were not elicited after DNA vaccination. The results are important for the development of both HSP and DNA-based immunomodulatory agents.
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Affiliation(s)
- D.S. Lima
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - C.R. ZÁrate-Bladés
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - P.R.M. Souza
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - A.P. Trombone
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - R.R. Santos-Junior
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University, Araraquara, São Paulo
| | - Lt. Brandão
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - A.P. Masson
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - V.L. Bonato
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - A.A.M. Coelho-Castelo
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - A. Sartori
- Department of Microbiology and Immunology, Biosciences Institute, São Paulo State University, Botucatu, São Paulo
| | - M. Vendramini
- Department of Pathology, University of São Paulo Medical School, São Paulo
| | - E.G. Soares
- Department of Pathology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo
| | - L.A. Benvenutti
- Department of Pathology, University of São Paulo Medical School, São Paulo
| | - C.L. Silva
- The Centre for Tuberculosis Research, Department of Biochemistry and Immunology, Medicine School of Ribeirão Preto, University of São Paulo, São Paulo
| | - V. Coelho
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo
- Institute for Investigation in Immunology, National Institute of Science and Technology -INCT, São Paulo, Brazil
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9
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Kar R, Nangpal P, Mathur S, Singh S, Tyagi AK. bioA mutant of Mycobacterium tuberculosis shows severe growth defect and imparts protection against tuberculosis in guinea pigs. PLoS One 2017; 12:e0179513. [PMID: 28658275 PMCID: PMC5489182 DOI: 10.1371/journal.pone.0179513] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 05/30/2017] [Indexed: 01/03/2023] Open
Abstract
Owing to the devastation caused by tuberculosis along with the unsatisfactory performance of the Bacillus Calmette–Guérin (BCG) vaccine, a more efficient vaccine than BCG is required for the global control of tuberculosis. A number of studies have demonstrated an essential role of biotin biosynthesis in the growth and survival of several microorganisms, including mycobacteria, through deletion of the genes involved in de novo biotin biosynthesis. In this study, we demonstrate that a bioA mutant of Mycobacterium tuberculosis (MtbΔbioA) is highly attenuated in the guinea pig model of tuberculosis when administered aerogenically as well as intradermally. Immunization with MtbΔbioA conferred significant protection in guinea pigs against an aerosol challenge with virulent M. tuberculosis, when compared with the unvaccinated animals. Booster immunization with MtbΔbioA offered no advantage over a single immunization. These experiments demonstrate the vaccinogenic potential of the attenuated M. tuberculosis bioA mutant against tuberculosis.
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Affiliation(s)
- Ritika Kar
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, India
| | - Prachi Nangpal
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, India
| | - Shubhita Mathur
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, India
| | - Swati Singh
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, India
| | - Anil K. Tyagi
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, India
- Vice Chancellor, Guru Gobind Singh Indraprastha University, Dwarka, New Delhi, India
- * E-mail:
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10
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Counoupas C, Pinto R, Nagalingam G, Hill-Cawthorne GA, Feng CG, Britton WJ, Triccas JA. Mycobacterium tuberculosis components expressed during chronic infection of the lung contribute to long-term control of pulmonary tuberculosis in mice. NPJ Vaccines 2016; 1:16012. [PMID: 29263854 PMCID: PMC5707878 DOI: 10.1038/npjvaccines.2016.12] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 05/27/2016] [Accepted: 07/05/2016] [Indexed: 11/09/2022] Open
Abstract
Tuberculosis (TB) remains a major cause of mortality and morbidity worldwide, yet current control strategies, including the existing BCG vaccine, have had little impact on disease control. The tubercle bacillus modifies protein expression to adapt to chronic infection of the host, and this can potentially be exploited to develop novel therapeutics. We identified the gene encoding the first step of the Mycobacterium tuberculosis sulphur assimilation pathway, cysD, as highly induced during chronic infection in the mouse lung, suggesting therapies based on CysD could be used to target infection. Vaccination with the composite vaccine CysVac2, a fusion of CysD and the immunogenic Ag85B of M. tuberculosis, resulted in the generation of multifunctional CD4+ T cells (interferon (IFN)-γ+TNF+IL-2+IL-17+) in the lung both pre- and post-aerosol challenge with M. tuberculosis. CysVac2 conferred significant protection against pulmonary M. tuberculosis challenge and was particularly effective at controlling late-stage infection, a property not shared by BCG. CysVac2 delivered as a booster following BCG vaccination afforded greater protection against M. tuberculosis challenge than BCG alone. The antigenic components of CysVac2 were conserved amongst M. tuberculosis strains, and protective efficacy afforded by CysVac2 was observed across varying murine MHC haplotypes. Strikingly, administration of CysVac2 to mice previously infected with M. tuberculosis reduced bacterial load and immunopathology in the lung compared with BCG-vaccinated mice. These results indicate that CysVac2 warrants further investigation to assess its potential to control pulmonary TB in humans.
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Affiliation(s)
- Claudio Counoupas
- Microbial Pathogenesis and Immunity Group, Department of Infectious Diseases and Immunology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
- Tuberculosis Research Program, Centenary Institute, University of Sydney, Sydney, NSW, Australia
| | - Rachel Pinto
- Microbial Pathogenesis and Immunity Group, Department of Infectious Diseases and Immunology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
- Tuberculosis Research Program, Centenary Institute, University of Sydney, Sydney, NSW, Australia
| | - Gayathri Nagalingam
- Microbial Pathogenesis and Immunity Group, Department of Infectious Diseases and Immunology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
- Tuberculosis Research Program, Centenary Institute, University of Sydney, Sydney, NSW, Australia
| | - Grant A Hill-Cawthorne
- Sydney Medical School and The Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW, Australia
- School of Public Health, University of Sydney, Sydney, NSW, Australia
| | - Carl G Feng
- Tuberculosis Research Program, Centenary Institute, University of Sydney, Sydney, NSW, Australia
- Sydney Medical School and The Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW, Australia
- Immunology and Host Defense Group, Department of Infectious Diseases and Immunology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Warwick J Britton
- Tuberculosis Research Program, Centenary Institute, University of Sydney, Sydney, NSW, Australia
- Sydney Medical School and The Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW, Australia
| | - James A Triccas
- Microbial Pathogenesis and Immunity Group, Department of Infectious Diseases and Immunology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
- Tuberculosis Research Program, Centenary Institute, University of Sydney, Sydney, NSW, Australia
- Sydney Medical School and The Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW, Australia
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11
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Elkington PT, Friedland JS. Permutations of time and place in tuberculosis. THE LANCET. INFECTIOUS DISEASES 2015; 15:1357-60. [PMID: 26321650 PMCID: PMC4872044 DOI: 10.1016/s1473-3099(15)00135-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 06/04/2015] [Accepted: 06/09/2015] [Indexed: 02/01/2023]
Abstract
Tuberculosis remains a global health pandemic. The current depiction of the Mycobacterium tuberculosis life cycle proposes that airborne bacilli are inhaled and phagocytosed by alveolar macrophages, resulting in the formation of a granuloma that ruptures into the airways to reinitiate the infectious cycle. However, this widely proposed model overlooks the fact, established 100 years ago, that the initial site of M tuberculosis implantation is in the lower zones of the lungs, whereas infectious cavitary pulmonary disease develops at the lung apices. The immunological events at these two pulmonary locations are different--cavitation only occurs in the apices and not in the bases. Yet the current conceptual model of tuberculosis renders the immunology of these two temporally and spatially separated events identical. One key consequence is that prevention of primary childhood tuberculosis at the lung bases is regarded as adequate immunological protection, but extensive evidence shows that greater immunity could predispose to immunopathology and transmission at the lung apex. A much greater understanding of time and place in the immunopathological mechanisms underlying human tuberculosis is needed before further pre-exposure vaccination trials can be done.
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Affiliation(s)
- Paul T Elkington
- Clinical and Experimental Sciences Academic Unit, Faculty of Medicine, University of Southampton, UK.
| | - Jon S Friedland
- Infectious Diseases and Immunity, Imperial College London, UK
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12
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Mayer-Barber KD, Barber DL. Innate and Adaptive Cellular Immune Responses to Mycobacterium tuberculosis Infection. Cold Spring Harb Perspect Med 2015; 5:a018424. [PMID: 26187873 PMCID: PMC4665043 DOI: 10.1101/cshperspect.a018424] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Host resistance to Mycobacterium tuberculosis (Mtb) infection requires the coordinated efforts of innate and adaptive immune cells. Diverse pulmonary myeloid cell populations respond to Mtb with unique contributions to both host-protective and potentially detrimental inflammation. Although multiple cell types of the adaptive immune system respond to Mtb infection, CD4 T cells are the principal antigen-specific cells responsible for containment of Mtb infection, but they can also be major contributors to disease during Mtb infection in several different settings. Here, we will discuss the role of different myeloid populations as well as the dual nature of CD4 T cells in Mtb infection with a primary focus on data generated using in vivo cellular immunological studies in experimental animal models and in humans when available.
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Affiliation(s)
- Katrin D Mayer-Barber
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Daniel L Barber
- T Lymphocyte Biology Unit, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Sequential chemoimmunotherapy of experimental visceral leishmaniasis using a single low dose of liposomal amphotericin B and a novel DNA vaccine candidate. Antimicrob Agents Chemother 2015; 59:5819-23. [PMID: 26055371 DOI: 10.1128/aac.00273-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 06/02/2015] [Indexed: 01/10/2023] Open
Abstract
Combination therapies for leishmaniasis, including drugs and immunomodulators, are one approach to shorten treatment courses and to improve the treatment of complex manifestations of the disease. We evaluated a novel T-cell-epitope-enriched DNA vaccine candidate (LEISHDNAVAX) as host-directed immunotherapy in combination with a standard antileishmanial drug in experimental visceral leishmaniasis. Here we show that the DNA vaccine candidate can boost the efficacy of a single suboptimal dose of liposomal amphotericin B in C57BL/6 mice.
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Doimo NTS, Zárate-Bladés CR, Rodrigues RF, Tefé-Silva C, Trotte MNS, Souza PRM, Soares LS, Rios WM, Floriano EM, Brandão IT, Masson AP, Coelho V, Ramos SG, Silva CL. Immunotherapy of tuberculosis with Mycobacterium leprae Hsp65 as a DNA vaccine triggers cross-reactive antibodies against mammalian Hsp60 but not pathological autoimmunity. Hum Vaccin Immunother 2014; 10:1238-43. [PMID: 24607935 DOI: 10.4161/hv.28249] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Despite substantial efforts in recent years toward the development of new vaccines and drugs against tuberculosis (TB), success has remained elusive. Immunotherapy of TB with mycobacterial Hsp65 as a DNA vaccine (DNA-hsp65) results in a reduction of systemic bacterial loads and lung tissue damage, but the high homology of Hsp65 with the mammalian protein raises concern that pathological autoimmune responses may also be triggered. We searched for autoimmune responses elicited by DNA-hsp65 immunotherapy in mice chronically infected with TB by evaluating the humoral immune response and comprehensive histopathology using stereology. Cross-reactive antibodies between mycobacterial and mammalian Hsp60/65 were detected; however, no signs of pathological autoimmunity were found up to 60 days after the end of the therapy.
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Affiliation(s)
- Nayara T S Doimo
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Carlos R Zárate-Bladés
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Rodrigo F Rodrigues
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Cristiane Tefé-Silva
- Department of Pathology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Marcele N S Trotte
- Veterinary Medical Department of Anatomical Pathology; State University of Rio de Janeiro; Rio de Janeiro, Brazil
| | - Patrícia R M Souza
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Luana S Soares
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Wendy M Rios
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Elaine M Floriano
- Department of Pathology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Izaira T Brandão
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Ana P Masson
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Verônica Coelho
- Laboratory of Immunology; Heart Institute (InCor); School of Medicine; University of São Paulo; São Paulo, Brazil; Institute for Investigation in Immunology (iii)-National Institute of Science and Technology; São Paulo, Brazil
| | - Simone G Ramos
- Department of Pathology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
| | - Celio L Silva
- The Centre for Tuberculosis Research; Department of Biochemistry and Immunology; Ribeirão Preto School of Medicine; University of São Paulo; São Paulo, Brazil
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16
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A single dose of a DNA vaccine encoding apa coencapsulated with 6,6'-trehalose dimycolate in microspheres confers long-term protection against tuberculosis in Mycobacterium bovis BCG-primed mice. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 20:1162-9. [PMID: 23740922 DOI: 10.1128/cvi.00148-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mycobacterium bovis BCG prime DNA (Mycobacterium tuberculosis genes)-booster vaccinations have been shown to induce greater protection against tuberculosis (TB) than BCG alone. This heterologous prime-boost strategy is perhaps the most realistic vaccination for the future of TB infection control, especially in countries where TB is endemic. Moreover, a prime-boost regimen using biodegradable microspheres seems to be a promising immunization to stimulate a long-lasting immune response. The alanine proline antigen (Apa) is a highly immunogenic glycoprotein secreted by M. tuberculosis. This study investigated the immune protection of Apa DNA vaccine against intratracheal M. tuberculosis challenge in mice on the basis of a heterologous prime-boost regimen. BALB/c mice were subcutaneously primed with BCG and intramuscularly boosted with a single dose of plasmid carrying apa and 6,6'-trehalose dimycolate (TDM) adjuvant, coencapsulated in microspheres (BCG-APA), and were evaluated 30 and 70 days after challenge. This prime-boost strategy (BCG-APA) resulted in a significant reduction in the bacterial load in the lungs, thus leading to better preservation of the lung parenchyma, 70 days postinfection compared to BCG vaccinated mice. The profound effect of this heterologous prime-boost regimen in the experimental model supports its development as a feasible strategy for prevention of TB.
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Colaco CA, Bailey CR, Walker KB, Keeble J. Heat shock proteins: stimulators of innate and acquired immunity. BIOMED RESEARCH INTERNATIONAL 2013; 2013:461230. [PMID: 23762847 PMCID: PMC3677648 DOI: 10.1155/2013/461230] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 05/09/2013] [Indexed: 12/26/2022]
Abstract
Adjuvants were reintroduced into modern immunology as the dirty little secret of immunologists by Janeway and thus began the molecular definition of innate immunity. It is now clear that the binding of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs) on antigen presenting cells (APCs) activates the innate immune response and provides the host with a rapid mechanism for detecting infection by pathogens and initiates adaptive immunity. Ironically, in addition to advancing the basic science of immunology, Janeway's revelation on induction of the adaptive system has also spurred an era of rational vaccine design that exploits PRRs. Thus, defined PAMPs that bind to known PRRs are being specifically coupled to antigens to improve their immunogenicity. However, while PAMPs efficiently activate the innate immune response, they do not mediate the capture of antigen that is required to elicit the specific responses of the acquired immune system. Heat shock proteins (HSPs) are molecular chaperones that are found complexed to client polypeptides and have been studied as potential cancer vaccines. In addition to binding PRRs and activating the innate immune response, HSPs have been shown to both induce the maturation of APCs and provide chaperoned polypeptides for specific triggering of the acquired immune response.
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Affiliation(s)
- Camilo A. Colaco
- ImmunoBiology Limited, Babraham Research Campus, Cambridge CB22 3AT, UK
| | | | | | - James Keeble
- NIBSC, Blanche Lane, South Mimms, Potters Bar EN6 3QG, UK
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Tameris MD, Hatherill M, Landry BS, Scriba TJ, Snowden MA, Lockhart S, Shea JE, McClain JB, Hussey GD, Hanekom WA, Mahomed H, McShane H. Safety and efficacy of MVA85A, a new tuberculosis vaccine, in infants previously vaccinated with BCG: a randomised, placebo-controlled phase 2b trial. Lancet 2013; 381:1021-8. [PMID: 23391465 PMCID: PMC5424647 DOI: 10.1016/s0140-6736(13)60177-4] [Citation(s) in RCA: 754] [Impact Index Per Article: 68.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND BCG vaccination provides incomplete protection against tuberculosis in infants. A new vaccine, modified Vaccinia Ankara virus expressing antigen 85A (MVA85A), was designed to enhance the protective efficacy of BCG. We aimed to assess safety, immunogenicity, and efficacy of MVA85A against tuberculosis and Mycobacterium tuberculosis infection in infants. METHODS In our double-blind, randomised, placebo-controlled phase 2b trial, we enrolled healthy infants (aged 4–6 months) without HIV infection who had previously received BCG vaccination. We randomly allocated infants (1:1), according to an independently generated sequence with block sizes of four, to receive one intradermal dose of MVA85A or an equal volume of Candida skin test antigen as placebo at a clinical facility in a rural region near Cape Town, South Africa. We actively followed up infants every 3 months for up to 37 months. The primary study outcome was safety (incidence of adverse and serious adverse events) in all vaccinated participants, but we also assessed efficacy in a protocol-defined group of participants who received at least one dose of allocated vaccine. The primary efficacy endpoint was incident tuberculosis incorporating microbiological, radiological, and clinical criteria, and the secondary efficacy endpoint was M tuberculosis infection according to QuantiFERON TB Gold In-tube conversion (Cellestis, Australia). This trial was registered with the South African National Clinical Trials Register (DOH-27-0109-2654) and with ClinicalTrials.gov on July 31, 2009, number NCT00953927. FINDINGS Between July 15, 2009, and May 4, 2011, we enrolled 2797 infants (1399 allocated MVA85A and 1398 allocated placebo). Median follow-up in the per-protocol population was 24·6 months (IQR 19·2–28·1), and did not differ between groups. More infants who received MVA85A than controls had at least one local adverse event (1251 [89%] of 1399 MVA85A recipients and 628 [45%] of 1396 controls who received the allocated intervention) but the numbers of infants with systemic adverse events (1120 [80%] and 1059 [76%]) or serious adverse events (257 [18%] and 258 (18%) did not differ between groups. None of the 648 serious adverse events in these 515 infants was related to MVA85A. 32 (2%) of 1399 MVA85A recipients met the primary efficacy endpoint (tuberculosis incidence of 1·15 per 100 person-years [95% CI 0·79 to 1·62]; with conversion in 178 [13%] of 1398 infants [95% CI 11·0 to 14·6]) as did 39 (3%) of 1395 controls (1·39 per 100 person-years [1·00 to 1·91]; with conversion in 171 [12%] of 1394 infants [10·6 to 14·1]). Efficacy against tuberculosis was 17·3% (95% CI −31·9 to 48·2) and against M tuberculosis infection was −3·8% (–28·1 to 15·9). INTERPRETATION MVA85A was well tolerated and induced modest cell-mediated immune responses. Reasons for the absence of MVA85A efficacy against tuberculosis or M tuberculosis infection in infants need exploration. FUNDING Aeras, Wellcome Trust, and Oxford-Emergent Tuberculosis Consortium (OETC).
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Affiliation(s)
- Michele D Tameris
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
- Correspondence to: Dr Michele D Tameris, South African Tuberculosis Vaccine Initiative (SATVI), Brewelskloof Hospital, Haarlem Street, Worcester 6850, South Africa
| | - Mark Hatherill
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
| | | | - Thomas J Scriba
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
| | | | - Stephen Lockhart
- Oxford-Emergent Tuberculosis Consortium, Wokingham, Berkshire, UK
- Emergent Product Development UK, Wokingham, Berkshire, UK
| | | | | | - Gregory D Hussey
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
- Vaccines for Africa, Institute of Infectious Disease and Molecular Medicine and Department of Medical Microbiology, University of Cape Town, Cape Town, South Africa
| | - Willem A Hanekom
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
| | - Hassan Mahomed
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
- Department of Health, Western Cape and Division of Community Health, Stellenbosch University, Stellenbosch, South Africa
| | - Helen McShane
- Jenner Institute, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
- Prof Helen McShane, University of Oxford, Jenner Institute, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
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Mixed-strain mycobacterium tuberculosis infections and the implications for tuberculosis treatment and control. Clin Microbiol Rev 2013; 25:708-19. [PMID: 23034327 DOI: 10.1128/cmr.00021-12] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Numerous studies have reported that individuals can simultaneously harbor multiple distinct strains of Mycobacterium tuberculosis. To date, there has been limited discussion of the consequences for the individual or the epidemiological importance of mixed infections. Here, we review studies that documented mixed infections, highlight challenges associated with the detection of mixed infections, and discuss possible implications of mixed infections for the diagnosis and treatment of patients and for the community impact of tuberculosis control strategies. We conclude by highlighting questions that should be resolved in order to improve our understanding of the importance of mixed-strain M. tuberculosis infections.
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The tuberculous granuloma: an unsuccessful host defence mechanism providing a safety shelter for the bacteria? Clin Dev Immunol 2012; 2012:139127. [PMID: 22811737 PMCID: PMC3395138 DOI: 10.1155/2012/139127] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 04/16/2012] [Accepted: 04/30/2012] [Indexed: 12/16/2022]
Abstract
One of the main features of the immune response to M. Tuberculosis is the formation of an organized structure called granuloma. It consists mainly in the recruitment at the infectious stage of macrophages, highly differentiated cells such as multinucleated giant cells, epithelioid cells and Foamy cells, all these cells being surrounded by a rim of lymphocytes. Although in the first instance the granuloma acts to constrain the infection, some bacilli can actually survive inside these structures for a long time in a dormant state. For some reasons, which are still unclear, the bacilli will reactivate in 10% of the latently infected individuals, escape the granuloma and spread throughout the body, thus giving rise to clinical disease, and are finally disseminated throughout the environment. In this review we examine the process leading to the formation of the granulomatous structures and the different cell types that have been shown to be part of this inflammatory reaction. We also discuss the different in vivo and in vitro models available to study this fascinating immune structure.
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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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22
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Yuan W, Dong N, Zhang L, Liu J, Lin S, Xiang Z, Qiao H, Tong W, Qin C. Immunogenicity and protective efficacy of a tuberculosis DNA vaccine expressing a fusion protein of Ag85B-Esat6-HspX in mice. Vaccine 2012; 30:2490-7. [DOI: 10.1016/j.vaccine.2011.06.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 05/19/2011] [Accepted: 06/09/2011] [Indexed: 12/23/2022]
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Abstract
Tuberculosis (TB) disease caused by Mycobacterium tuberculosis (M. tb) remains one of the leading infectious causes of death and disease throughout the world. The only licensed vaccine, Mycobacterium bovis bacille Calmette-Guérin (BCG) confers highly variable protection against pulmonary disease. An effective vaccination regimen would be the most efficient way to control the epidemic. However, BCG does confer consistent and reliable protection against disseminated disease in childhood, and most TB vaccine strategies being developed incorporate BCG to retain this protection. Cellular immunity is necessary for protection against TB and all the new vaccines in development are focused on inducing a strong and durable cellular immune response. There are two main strategies being pursued in TB vaccine development. The first is to replace BCG with an improved whole organism mycobacterial priming vaccine, which is either a recombinant BCG or an attenuated strain of M. tb. The second is to develop a subunit boosting vaccine, which is designed to be administered after BCG vaccination, and to enhance the protective efficacy of BCG. This article reviews the leading candidate vaccines in development and considers the current challenges in the field with regard to efficacy testing.
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Affiliation(s)
- Helen McShane
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK.
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24
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Ahn SS, Jeon BY, Kim KS, Kwack JY, Lee EG, Park KS, Sung YC, Cho SN. Mtb32 is a promising tuberculosis antigen for DNA vaccination in pre- and post-exposure mouse models. Gene Ther 2011; 19:570-5. [PMID: 21956689 DOI: 10.1038/gt.2011.140] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Identification of antigens that provide protective immunity via prophylactic and therapeutic vaccination against Mycobacterium tuberculosis is critical for the development of subunit vaccines for tuberculosis (TB). In this study, we performed a head-to-head comparison of seven well-known TB antigens delivered by DNA vaccine, and evaluated their respective immunogenicities and protective efficacies in pre- and post-exposure mouse models. All TB antigens were designed as a chimeric fusion with Flt3-L to enhance antigen-specific T-cell immunity upon vaccination. Prophylactic vaccination with the Flt3L (F)-Mtb32 DNA vaccine elicited significant protection in both the spleen and lungs against M. tuberculosis challenge, comparable to the Bacillus Calmette-Guerin vaccine. F-Ag85A and F-Mtb32 DNA vaccines, in combination with chemotherapy, reduced the bacterial burden to undetectable levels in the lungs of all mice infected with M. tuberculosis. These data collectively indicate that the F-Mtb32 DNA vaccine confers the most efficient protective immunity that suppresses bacterial growth in the active or latent status of M. tuberculosis.
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Affiliation(s)
- S-S Ahn
- Division of Molecular and Life Sciences, Postech Biotech Center, Pohang University of Science and Technology, Pohang, Korea
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Dey B, Jain R, Gupta UD, Katoch VM, Ramanathan VD, Tyagi AK. A booster vaccine expressing a latency-associated antigen augments BCG induced immunity and confers enhanced protection against tuberculosis. PLoS One 2011; 6:e23360. [PMID: 21858087 PMCID: PMC3157374 DOI: 10.1371/journal.pone.0023360] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 07/13/2011] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND In spite of a consistent protection against tuberculosis (TB) in children, Mycobacterium bovis Bacille Calmette-Guerin (BCG) fails to provide adequate protection against the disease in adults as well as against reactivation of latent infections or exogenous reinfections. It has been speculated that failure to generate adequate memory T cell response, elicitation of inadequate immune response against latency-associated antigens and inability to impart long-term immunity against M. tuberculosis infections are some of the key factors responsible for the limited efficiency of BCG in controlling TB. METHODS/PRINCIPAL FINDINGS In this study, we evaluated the ability of a DNA vaccine expressing α-crystallin--a key latency antigen of M. tuberculosis to boost the BCG induced immunity. 'BCG prime-DNA boost' regimen (B/D) confers robust protection in guinea pigs along with a reduced pathology in comparison to BCG vaccination (1.37 log(10) and 1.96 log(10) fewer bacilli in lungs and spleen, respectively; p<0.01). In addition, B/D regimen also confers enhanced protection in mice. Further, we show that B/D immunization in mice results in a heightened frequency of PPD and antigen specific multi-functional CD4 T cells (3(+)) simultaneously producing interferon (IFN)γ, tumor necrosis factor (TNF)α and interleukin (IL)2. CONCLUSIONS/SIGNIFICANCE These results clearly indicate the superiority of α-crystallin based B/D regimen over BCG. Our study, also demonstrates that protection against TB is predictable by an increased frequency of 3(+) Th1 cells with superior effector functions. We anticipate that this study would significantly contribute towards the development of superior booster vaccines for BCG vaccinated individuals. In addition, this regimen can also be expected to reduce the risk of developing active TB due to reactivation of latent infection.
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Affiliation(s)
- Bappaditya Dey
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India
| | - Ruchi Jain
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India
| | - Umesh D. Gupta
- National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra, Uttar Pradesh, India
| | - V. M. Katoch
- National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra, Uttar Pradesh, India
| | - V. D. Ramanathan
- Department of Clinical Pathology, Tuberculosis Research Center, Chennai, Tamil Nadu, India
| | - Anil K. Tyagi
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India
- * E-mail:
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Giri PK, Verma I, Khuller GK. Adjunct immunotherapy with Ag85 complex proteins based subunit vaccine in a murine model of Mycobacterium tuberculosis infection. Immunotherapy 2011; 1:31-7. [PMID: 20635971 DOI: 10.2217/1750743x.1.1.31] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This study was designed to evaluate the immunotherapeutic potential of Mycobacterium tuberculosis Ag85AB emulsified with unmethylated CpG motif-containing oligonucleotide (CpG-ODN) and dimethyldioctadecylammonium bromide (DDA) adjuvants (Ag85AB-CpG-DDA) in conjunction with antituberculous drugs. Ag85 complex proteins of M. tuberculosis purified from total culture filtrate and purified proteins were emulsified with CpG-ODN and DDA adjuvants. Mice were infected with M. tuberculosis H37 Rv and left for 30 days to establish infection. These mice were named 'tuberculous mice'. Tuberculous mice were treated with Ag85AB-CpG-DDA alone or in conjunction with antituberculous drugs. Treatment of tuberculous mice with Ag85AB-CpG-DDA in conjunction with antituberculous drugs reduced significant bacilli burden in lung and spleen. Moreover, treatment of tuberculous mice with Ag85AB-CpG-DDA induced higher production of type-I cytokines, generated more CD44-positive T cells and suppresses secretion of IL-4 as compared with untreated animals. In conclusion, this study shows that Ag85AB-CpG-DDA formulation may act as a potential future therapeutic regimen in conjunction with antituberculous drugs.
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Cruz A, Fraga AG, Fountain JJ, Rangel-Moreno J, Torrado E, Saraiva M, Pereira DR, Randall TD, Pedrosa J, Cooper AM, Castro AG. Pathological role of interleukin 17 in mice subjected to repeated BCG vaccination after infection with Mycobacterium tuberculosis. ACTA ACUST UNITED AC 2010; 207:1609-16. [PMID: 20624887 PMCID: PMC2916141 DOI: 10.1084/jem.20100265] [Citation(s) in RCA: 197] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Infection usually leads to the development of acquired immune responses associated with clearance or control of the infecting organism. However, if not adequately regulated, immune-mediated pathology can result. Tuberculosis is a worldwide threat, and development of an effective vaccine requires that the protective immune response to Mycobacterium tuberculosis (Mtb) be dissected from the pathological immune response. This distinction is particularly important if new vaccines are to be delivered to Mtb-exposed individuals, as repeated antigenic exposure can lead to pathological complications. Using a model wherein mice are vaccinated with bacille Calmette-Guérin after Mtb infection, we show that repeated vaccination results in increased IL-17, tumor necrosis factor, IL-6, and MIP-2 expression, influx of granulocytes/neutrophils, and lung tissue damage. This pathological response is abrogated in mice deficient in the gene encoding IL-23p19 or in the presence of IL-17–blocking antibody. This finding that repeated exposure to mycobacterial antigen promotes enhanced IL-17–dependent pathological consequences has important implications for the design of effective vaccines against Mtb.
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Affiliation(s)
- Andrea Cruz
- Life and Health Sciences Research Institute, School of Health Sciences, University of Minho, 4710-057 Braga, Portugal
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Nagata T, Koide Y. [T-cell-oriented vaccination against Mycobacterium tuberculosis]. Nihon Saikingaku Zasshi 2010; 65:309-24. [PMID: 20505270 DOI: 10.3412/jsb.65.309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Toshi Nagata
- Department of Health Science, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu
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Immunogenicity and protective efficacy of mycobacterial DNA vaccines incorporating plasmid-encoded cytokines against Mycobacterium bovis. Immunol Cell Biol 2010; 88:651-7. [DOI: 10.1038/icb.2010.25] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chen L, Xu M, Wang ZY, Chen BW, Du WX, Su C, Shen XB, Zhao AH, Dong N, Wang YJ, Wang GZ. The development and preliminary evaluation of a new Mycobacterium tuberculosis vaccine comprising Ag85b, HspX and CFP-10:ESAT-6 fusion protein with CpG DNA and aluminum hydroxide adjuvants. ACTA ACUST UNITED AC 2010; 59:42-52. [PMID: 20298499 DOI: 10.1111/j.1574-695x.2010.00660.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ag85b and HspX of Mycobacterium tuberculosis (Mtb) (H37Rv) were expressed and purified in this study. These two proteins were combined with another fusion protein CFP-10:ESAT-6 (C/E) (Ag), then mixed with the adjuvants CpG DNA and aluminum hydroxide and used to vaccinate mice and guinea pigs challenged with Mtb (H37Rv). The number of spleen lymphocytes secreting Ag85b, HspX and C/E-specific interferon-gamma were significantly higher in the Ag+Al+CpG group than in the Ag and CpG groups. The combination of Ag, Al and CpG induced the highest concentrations of anti-Ag85b, anti-HspX and anti-C/E immunoglobulin G in mouse serum. Mouse peritoneal macrophages from the Ag+Al+CpG group secreted significantly higher levels of interleukin-12 compared with macrophages from the other groups. The total mean liver, lung and spleen lesion scores and bacterial loads in the spleen in guinea pigs vaccinated with Ag+Al+CpG were lower than those of the other groups, but no significant difference was found. These results show that the mixture of Ag85b, HspX and C/E with a combination of CpG and aluminum adjuvants can induce both humoral and cellular immune responses in mice, whereas it plays only a small role in the control of disease progression in guinea pigs challenged with Mtb.
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Affiliation(s)
- Lei Chen
- School of Public Health, Shandong University, Ji'nan, China
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Singhal N, Bisht D, Joshi B. Immunoprophylaxis of tuberculosis: an update of emerging trends. Arch Immunol Ther Exp (Warsz) 2010; 58:97-106. [PMID: 20140756 DOI: 10.1007/s00005-010-0068-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Accepted: 07/06/2009] [Indexed: 11/25/2022]
Abstract
Developing effective prophylactics to combat tuberculosis is currently in an exploratory stage. The HIV pandemic and emergence of multi- and extensively drug-resistant strains of Mycobacterium tuberculosis indicate that the current preventive measures against this ever-evolving pathogen are inadequate. The currently available vaccine BCG in its present form affords variable protection which usually wanes with aging. Various reasons have been cited to explain the discrepancies in the efficacy of BCG, including generic differences in the different BCG vaccine strains used in immunization program throughout the world. The low efficacy of BCG vaccine has promoted the search for novel vaccines for tuberculosis. The search strategies aim at completely replacing the existing vaccine and/or augmenting/improving the current BCG vaccine. Among new vaccine candidates are live attenuated M. tuberculosis vaccines, recombinant BCG, DNA vaccines, subunit vaccine, and fusion protein-based vaccines. More than 200 new vaccine candidates have been developed as a result of research work over the past few years. To date, at least eight vaccine candidates are undergoing clinical evaluation, with a few of them successfully qualifying in the first phase of clinical testing. These recent advances present an optimistic insight whereby a new tuberculosis vaccine might be expected to be available for public use in the next few years.
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Affiliation(s)
- Neelja Singhal
- Department of Biochemistry, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Indian Council of Medical Research, Tajganj, Agra 282001, India
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Verma I, Grover A. Antituberculous vaccine development: a perspective for the endemic world. Expert Rev Vaccines 2010; 8:1547-53. [PMID: 19863247 DOI: 10.1586/erv.09.111] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Several new antituberculous vaccine candidates that are effective against primary infection in preclinical animal models have now entered the early phases of clinical trials. Many of these clinical trials involve subunit vaccines, recombinant bacillus Calmette-Guérin (BCG), or improvement of BCG immunity by boosting with subunit vaccines or recombinant viral vectors expressing immunodominant TB antigens. The burning question at this stage is: will the current vaccines be effective in the endemic world where the diverse and complex challenges of TB exist? These challenges include protection of those individuals who are already vaccinated with BCG, those already exposed to environmental mycobacteria and those infected with latent TB or HIV. This review focuses on the available BCG vaccine, new TB vaccines in the pipeline and what type of vaccines are actually needed in high-burden endemic countries.
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Affiliation(s)
- Indu Verma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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Dey B, Jain R, Khera A, Rao V, Dhar N, Gupta UD, Katoch VM, Ramanathan VD, Tyagi AK. Boosting with a DNA vaccine expressing ESAT-6 (DNAE6) obliterates the protection imparted by recombinant BCG (rBCGE6) against aerosol Mycobacterium tuberculosis infection in guinea pigs. Vaccine 2009; 28:63-70. [PMID: 19835824 DOI: 10.1016/j.vaccine.2009.09.121] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Accepted: 09/25/2009] [Indexed: 12/12/2022]
Abstract
Owing to its highly immunodominant nature and ability to induce long-lived memory immunity, ESAT-6, a prominent antigen of Mycobacterium tuberculosis, has been employed in several approaches to develop tuberculosis vaccines. Here, for the first time, we combined ESAT-6 based recombinant BCG (rBCG) and DNA vaccine (DNAE6) in a prime boost approach. Interestingly, in spite of inducing an enhanced antigen specific IFN-gamma response in mice, a DNAE6 booster completely obliterated the protection imparted by rBCG against tuberculosis in guinea pigs. Analysis of immunopathology and cytokine responses suggests involvement of an exaggerated immunity behind the lack of protection imparted by this regimen.
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Affiliation(s)
- Bappaditya Dey
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India
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Silva BDDS, da Silva EB, do Nascimento IP, dos Reis MCG, Kipnis A, Junqueira-Kipnis AP. MPT-51/CpG DNA vaccine protects mice against Mycobacterium tuberculosis. Vaccine 2009; 27:4402-7. [DOI: 10.1016/j.vaccine.2009.05.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 05/06/2009] [Accepted: 05/14/2009] [Indexed: 11/16/2022]
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Alekseeva E, Sominskaya I, Skrastina D, Egorova I, Starodubova E, Kushners E, Mihailova M, Petrakova N, Bruvere R, Kozlovskaya T, Isaguliants M, Pumpens P. Enhancement of the expression of HCV core gene does not enhance core-specific immune response in DNA immunization: advantages of the heterologous DNA prime, protein boost immunization regimen. GENETIC VACCINES AND THERAPY 2009; 7:7. [PMID: 19505299 PMCID: PMC2702340 DOI: 10.1186/1479-0556-7-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 06/08/2009] [Indexed: 01/17/2023]
Abstract
BACKGROUND Hepatitis C core protein is an attractive target for HCV vaccine aimed to exterminate HCV infected cells. However, although highly immunogenic in natural infection, core appears to have low immunogenicity in experimental settings. We aimed to design an HCV vaccine prototype based on core, and devise immunization regimens that would lead to potent anti-core immune responses which circumvent the immunogenicity limitations earlier observed. METHODS Plasmids encoding core with no translation initiation signal (pCMVcore); with Kozak sequence (pCMVcoreKozak); and with HCV IRES (pCMVcoreIRES) were designed and expressed in a variety of eukaryotic cells. Polyproteins corresponding to HCV 1b amino acids (aa) 1-98 and 1-173 were expressed in E. coli. C57BL/6 mice were immunized with four 25-microg doses of pCMVcoreKozak, or pCMV (I). BALB/c mice were immunized with 100 microg of either pCMVcore, or pCMVcoreKozak, or pCMVcoreIRES, or empty pCMV (II). Lastly, BALB/c mice were immunized with 20 microg of core aa 1-98 in prime and boost, or with 100 microg of pCMVcoreKozak in prime and 20 microg of core aa 1-98 in boost (III). Antibody response, [3H]-T-incorporation, and cytokine secretion by core/core peptide-stimulated splenocytes were assessed after each immunization. RESULTS Plasmids differed in core-expression capacity: mouse fibroblasts transfected with pCMVcore, pCMVcoreIRES and pCMVcoreKozak expressed 0.22 +/- 0.18, 0.83 +/- 0.5, and 13 +/- 5 ng core per cell, respectively. Single immunization with highly expressing pCMVcoreKozak induced specific IFN-gamma and IL-2, and weak antibody response. Single immunization with plasmids directing low levels of core expression induced similar levels of cytokines, strong T-cell proliferation (pCMVcoreIRES), and antibodies in titer 103(pCMVcore). Boosting with pCMVcoreKozak induced low antibody response, core-specific T-cell proliferation and IFN-gamma secretion that subsided after the 3rd plasmid injection. The latter also led to a decrease in specific IL-2 secretion. The best was the heterologous pCMVcoreKozak prime/protein boost regiment that generated mixed Th1/Th2-cellular response with core-specific antibodies in titer >or= 3 x 10(3). CONCLUSION Thus, administration of highly expressed HCV core gene, as one large dose or repeated injections of smaller doses, may suppress core-specific immune response. Instead, the latter is induced by a heterologous DNA prime/protein boost regiment that circumvents the negative effects of intracellular core expression.
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Affiliation(s)
- Ekaterina Alekseeva
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga, LV-1067, Latvia.
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Domingo M, Gil O, Serrano E, Guirado E, Nofrarias M, Grassa M, Cáceres N, Pérez B, Vilaplana C, Cardona PJ. Effectiveness and Safety of a Treatment Regimen Based on Isoniazid Plus Vaccination withMycobacterium tuberculosiscells’ Fragments: Field-Study with NaturallyMycobacterium caprae-Infected Goats. Scand J Immunol 2009; 69:500-7. [DOI: 10.1111/j.1365-3083.2009.02251.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Tuberculosis is primarily a disease of the lung, and dissemination of the disease depends on productive infection of this critical organ. Upon aerosol infection with Mycobacterium tuberculosis (Mtb), the acquired cellular immune response is slow to be induced and to be expressed within the lung. This slowness allows infection to become well established; thus, the acquired response is expressed in an inflammatory site that has been initiated and modulated by the bacterium. Mtb has a variety of surface molecules that interact with the innate response, and this interaction along with the autoregulation of the immune response by several mechanisms results in less-than-optimal control of bacterial growth. To improve current vaccine strategies, we must understand the factors that mediate induction, expression, and regulation of the immune response in the lung. We must also determine how to induce both known and novel immunoprotective responses without inducing immunopathologic consequences.
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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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Cardona P, Asensio JG, Arbués A, Otal I, Lafoz C, Gil O, Caceres N, Ausina V, Gicquel B, Martin C. Extended safety studies of the attenuated live tuberculosis vaccine SO2 based on phoP mutant. Vaccine 2009; 27:2499-505. [DOI: 10.1016/j.vaccine.2009.02.060] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Revised: 01/15/2009] [Accepted: 02/18/2009] [Indexed: 11/24/2022]
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40
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Henao-Tamayo M, Palaniswamy GS, Smith EE, Shanley CA, Wang B, Orme IM, Basaraba RJ, DuTeau NM, Ordway D. Post-exposure vaccination against Mycobacterium tuberculosis. Tuberculosis (Edinb) 2009; 89:142-8. [PMID: 19264552 DOI: 10.1016/j.tube.2009.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Revised: 12/17/2008] [Accepted: 01/06/2009] [Indexed: 10/21/2022]
Abstract
Enhancing immunity to tuberculosis in animal models after exposure to the infection has proved difficult. In this study we used a newly described flow cytometric technique to monitor changes in cell populations accumulating in the lungs of guinea pigs challenged by low-dose aerosol infection with Mycobacterium tuberculosis and vaccinated 10 days later. On day 40 after infection the fusion protein F36 and a pool of Ag85A and ESAT6 vaccines had significant effects on the bacterial load, showed increased expression of the activation marker CD45+ on CD4+ T cells, and reduced numbers of heterophils. Lung pathology and pathology scores were marginally improved in animals given these vaccines, but lymph node pathology was not influenced. Despite early effects no changes in long-term survival were seen. These results suggest that a single post-exposure vaccination can initially slow the disease process. However, this effect is transient, but this could be of use in an multidrug resistant/extremely drug resistant outbreak situation because it could potentially slow the infection long enough to complete drug susceptibility testing and initiate effective chemotherapy.
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Cooper AM, Khader SA. The role of cytokines in the initiation, expansion, and control of cellular immunity to tuberculosis. Immunol Rev 2009; 226:191-204. [PMID: 19161425 DOI: 10.1111/j.1600-065x.2008.00702.x] [Citation(s) in RCA: 250] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Tuberculosis (TB) results from an interaction between a potent immune response and a chronically persistent pathogen. The ability of Mycobacterium tuberculosis (Mtb) to induce a strong immune response while being able to resist the ability of the host to clear bacteria provides an excellent tool with which to investigate the role of specific cytokine pathways on the induction, expansion, and control of the effector T-cell response. In this review, the role of interleukin-12p40 (IL-12p40), IL-12p70, IL-23, and IL-27 in the immune response to Mtb are described. We show that IL-12(p40)(2) acts to mediate the activation of dendritic cells to become responsive to homeostatic chemokines. We also show that IL-12p70 is required for the optimal interferon-gamma (IFN-gamma) T-cell response, which is required for control of Mtb growth. IL-23 can induce IFN-gamma responses in the lung if IL-12 is not present, but its major role is in supporting the IL-17 response within the lung. Neither IL-23 nor IL-17 is required for early control of Mtb in the lung. IL-23 and IL-17, however, can be instrumental in vaccine-induced protection. Finally, IL-27 limits protective immunity in the lung, but it is also required for long-term survival. These cytokines are therefore key players in the immune response to TB.
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Sander CR, Pathan AA, Beveridge NER, Poulton I, Minassian A, Alder N, Van Wijgerden J, Hill AVS, Gleeson FV, Davies RJO, Pasvol G, McShane H. Safety and immunogenicity of a new tuberculosis vaccine, MVA85A, in Mycobacterium tuberculosis-infected individuals. Am J Respir Crit Care Med 2009; 179:724-33. [PMID: 19151191 DOI: 10.1164/rccm.200809-1486oc] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE An effective new tuberculosis (TB) vaccine regimen must be safe in individuals with latent TB infection (LTBI) and is a priority for global health care. OBJECTIVES To evaluate the safety and immunogenicity of a leading new TB vaccine, recombinant Modified Vaccinia Ankara expressing Antigen 85A (MVA85A) in individuals with LTBI. METHODS An open-label, phase I trial of MVA85A was performed in 12 subjects with LTBI recruited from TB contact clinics in Oxford and London or by poster advertisements in Oxford hospitals. Patients were assessed clinically and had blood samples drawn for immunological analysis over a 52-week period after vaccination with MVA85A. Thoracic computed tomography scans were performed at baseline and at 10 weeks after vaccination. Safety of MVA85A was assessed by clinical, radiological, and inflammatory markers. The immunogenicity of MVA85A was assessed by IFNgamma and IL-2 ELISpot assays and FACS. MEASUREMENTS AND MAIN RESULTS MVA85A was safe in subjects with LTBI, with comparable adverse events to previous trials of MVA85A. There were no clinically significant changes in inflammatory markers or thoracic computed tomography scans after vaccination. MVA85A induced a strong antigen-specific IFN-gamma and IL-2 response that was durable for 52 weeks. The magnitude of IFN-gamma response was comparable to previous trials of MVA85A in bacillus Calmette-Guérin-vaccinated individuals. Antigen 85A-specific polyfunctional CD4(+) T cells were detectable prior to vaccination with statistically significant increases in cell numbers after vaccination. CONCLUSIONS MVA85A is safe and highly immunogenic in individuals with LTBI. These results will facilitate further trials in TB-endemic areas. Clinical trial registered with www.clinicaltrials.gov (NCT00456183).
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Affiliation(s)
- Clare R Sander
- Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford, Oxford OX3 7LJ, UK
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Therapeutic efficacy of a tuberculosis DNA vaccine encoding heat shock protein 65 of Mycobacterium tuberculosis and the human interleukin 2 fusion gene. Tuberculosis (Edinb) 2009; 89:54-61. [DOI: 10.1016/j.tube.2008.09.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2008] [Revised: 09/01/2008] [Accepted: 09/17/2008] [Indexed: 01/08/2023]
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Beverley PCL, Tchilian EZ. Lessons for tuberculosis vaccines from respiratory virus infection. Expert Rev Vaccines 2008; 7:1165-72. [PMID: 18844591 DOI: 10.1586/14760584.7.8.1165] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There is a worldwide epidemic of increasingly drug-resistant TB. Bacillus Calmette-Guérin vaccination provides partial protection against disseminated disease in infants but poor protection against later pulmonary TB. Cell-mediated protection against respiratory virus infections requires the presence of T cells in lung tissues, and the most effective prime-boost immunizations for Mycobacterium tuberculosis also induce lung-resident lymphocytes. These observations need to be taken into account when designing future vaccines against M. tuberculosis.
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Affiliation(s)
- Peter Charles Leonard Beverley
- The University of Oxford, Nuffield Department of Clinical Medicine, Edward Jenner Institute for Vaccine Research, Compton, Berkshire, RG20 7NN, UK.
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Derrick SC, Perera LP, Dheenadhayalan V, Yang A, Kolibab K, Morris SL. The safety of post-exposure vaccination of mice infected with Mycobacterium tuberculosis. Vaccine 2008; 26:6092-8. [PMID: 18809446 DOI: 10.1016/j.vaccine.2008.09.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Revised: 08/20/2008] [Accepted: 09/02/2008] [Indexed: 11/29/2022]
Abstract
New post-exposure tuberculosis vaccination strategies are being developed to prevent disease in individuals latently infected with Mycobacterium tuberculosis. However, concerns about the potential induction of deleterious Koch-like reactions after immunization of persons with latent tuberculosis has limited progress in assessing the effectiveness of post-exposure vaccination. To evaluate the safety of immunization after M. tuberculosis infection, two mouse models were established, a drug treatment low bacterial burden model and an active disease model. Twelve different M. tuberculosis antigen preparations and vaccines (including DNA, subunit, viral vectored, and live, attenuated vaccines) were evaluated using these mouse models. In the low bacterial burden model, post-exposure vaccination did not induce significant reactivational disease and only injection of BCG evoked increases in lung inflammatory responses at 1 month after the immunizations. Additionally, although significant increases in lung inflammation were seen for animals injected with the hps65 DNA vaccine or a M. tuberculosis culture supernatant preparation, no differences in the survival periods were detected between vaccinated and non-vaccinated mice at 10 months post-immunization using the low bacterial burden model. For the active disease model, significantly more lung inflammation was observed at 1 month after administration of the hsp65 DNA vaccine but none of the antigen preparations tested increased the lung bacterial burdens at this early time point. Furthermore, vaccination of diseased mice with BCG or TB DNA vaccines did not significantly affect mortality rates compared to non-vaccinated controls at 10 months post-immunization. Overall, these data suggest that while the potential risk of inducing Koch-like reactions is low after immunization of persons with latent tuberculosis, extreme caution is still needed as post-exposure vaccines progress from pre-clinical experiments into the initial phases of clinical testing.
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Affiliation(s)
- Steven C Derrick
- Laboratory of Mycobacterial Diseases and Cellular Immunology, Center for Biologics Evaluation and Research, United States Food and Drug Administration, Bethesda, MD 20892, USA.
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Rosada RS, de la Torre LG, Frantz FG, Trombone APF, Zárate-Bladés CR, Fonseca DM, Souza PRM, Brandão IT, Masson AP, Soares EG, Ramos SG, Faccioli LH, Silva CL, Santana MHA, Coelho-Castelo AAM. Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes. BMC Immunol 2008; 9:38. [PMID: 18647414 PMCID: PMC2500095 DOI: 10.1186/1471-2172-9-38] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Accepted: 07/22/2008] [Indexed: 02/19/2023] Open
Abstract
Background The greatest challenges in vaccine development include optimization of DNA vaccines for use in humans, creation of effective single-dose vaccines, development of delivery systems that do not involve live viruses, and the identification of effective new adjuvants. Herein, we describe a novel, simple technique for efficiently vaccinating mice against tuberculosis (TB). Our technique consists of a single-dose, genetic vaccine formulation of DNA-hsp65 complexed with cationic liposomes and administered intranasally. Results We developed a novel and non-toxic formulation of cationic liposomes, in which the DNA-hsp65 vaccine was entrapped (ENTR-hsp65) or complexed (COMP-hsp65), and used to immunize mice by intramuscular or intranasal routes. Although both liposome formulations induced a typical Th1 pattern of immune response, the intramuscular route of delivery did not reduce the number of bacilli. However, a single intranasal immunization with COMP-hsp65, carrying as few as 25 μg of plasmid DNA, leads to a remarkable reduction of the amount of bacilli in lungs. These effects were accompanied by increasing levels of IFN-γ and lung parenchyma preservation, results similar to those found in mice vaccinated intramuscularly four times with naked DNA-hsp65 (total of 400 μg). Conclusion Our objective was to overcome the significant obstacles currently facing DNA vaccine development. Our results in the mouse TB model showed that a single intranasal dose of COMP-hsp65 elicited a cellular immune response that was as strong as that induced by four intramuscular doses of naked-DNA. This formulation allowed a 16-fold reduction in the amount of DNA administered. Moreover, we demonstrated that this vaccine is safe, biocompatible, stable, and easily manufactured at a low cost. We believe that this strategy can be applied to human vaccines to TB in a single dose or in prime-boost protocols, leading to a tremendous impact on the control of this infectious disease.
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Affiliation(s)
- Rogério S Rosada
- Núcleo de Pesquisas em Tuberculose, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, São Paulo,
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Yu DH, Hu XD, Cai H. Efficient tuberculosis treatment in mice using chemotherapy and immunotherapy with the combined DNA vaccine encoding Ag85B, MPT-64 and MPT-83. Gene Ther 2008; 15:652-9. [DOI: 10.1038/gt.2008.13] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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48
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Murphy D, Corner LAL, Gormley E. Adverse reactions to Mycobacterium bovis bacille Calmette-Guérin (BCG) vaccination against tuberculosis in humans, veterinary animals and wildlife species. Tuberculosis (Edinb) 2008; 88:344-57. [PMID: 18222731 DOI: 10.1016/j.tube.2007.11.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Revised: 11/27/2007] [Accepted: 11/29/2007] [Indexed: 11/19/2022]
Abstract
The Mycobacterium bovis strain, bacille Calmette-Guérin (BCG) is one of the most widely used human vaccines and remains one of the safest vaccines available. It has been used in human populations for over 80 years and 100 million children receive the vaccine annually. It has also been employed extensively for vaccine studies in laboratory animal hosts and is currently being developed for use in a variety of livestock and wild animals. Despite the large number of doses delivered since is first usage in 1921, reports of adverse reactions arising from the use of the BCG vaccine are relatively uncommon and where serious reactions do occur they are often the result of vaccination of immuno-compromised individuals. Factors that may influence the development of adverse reactions to BCG include the potency and dose of the vaccine strain, the route of delivery, the age and immune status of the host, and the skill levels of the operator administering the vaccine. Circumstances affecting the notification of adverse reactions include the lack of clear case definitions of abnormal vaccine reactions, and a scarcity of systematic surveillance and functioning reporting systems. With continued use of the BCG and the development of a new generation of prophylactic and therapeutic vaccines against tuberculosis in different host species, the risk factors associated with adverse reactions may need to be reappraised.
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Affiliation(s)
- D Murphy
- Veterinary Sciences Centre, School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
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Doherty TM, Dietrich J, Billeskov R. Tuberculosis subunit vaccines: from basic science to clinical testing. Expert Opin Biol Ther 2007; 7:1539-49. [PMID: 17916046 DOI: 10.1517/14712598.7.10.1539] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
More than 80 years after the introduction of Bacillus Calmette-GuErin, the first tuberculosis vaccine, new vaccines for tuberculosis are finally in clinical trials. The selection of antigens on which new subunit vaccines are based represent the first fulfillment of the promise of proteomics and genomics, and the delivery systems for these antigens are likewise the first fruits of the improved understanding of how the host immune system recognizes pathogens. However, clinical trials are still at Phase I and there remain formidable obstacles to the registration of the first new TB vaccines. Here the authors review the vaccines in clinical trials and discuss the different approaches they take to stimulating immunity to Mycobacterium tuberculosis infection, focusing on recombinant subunit vaccines. The challenges that confront these approaches and how they are being addressed are then discussed.
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Affiliation(s)
- T Mark Doherty
- Statens Serum Institute, Department of Infectious Disease Immunology, Copenhagen, Denmark.
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Abstract
The world is witnessing an escalation of the tuberculosis (TB) epidemic, particularly in sub-Saharan Africa and South-East Asia. The problem has been compounded by the evolution of the human immunodeficiency virus pandemic, the increase in multidrug-resistant TB and the emergence of extensively drug-resistant TB. This has led to renewed interest in vaccines aimed at preventing tuberculosis. The current Bacille Calmette-Guérin (BCG) vaccine prevents the invasive complications of childhood tuberculosis, such as meningitis and miliary disease, but provides variable protection against adult pulmonary disease. This review discusses the history of the BCG vaccine, the reasons for its variable efficacy, protective immunity and TB, and the evolution of and obstacles to development of new candidate vaccines. Several new TB vaccines have demonstrated promising results in animal models; a number have gone into phase I clinical trials in humans, and it is anticipated that phase III trials will commence by 2009. Licensing of an effective new TB vaccine by 2015 is thus a possibility.
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Affiliation(s)
- Gregory Hussey
- South African Tuberculosis Vaccine Initiative, University of Cape Town, Anzio Road, Observatory, 7925, South Africa.
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