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Cheng A, Holland SM. Anti-cytokine autoantibodies: mechanistic insights and disease associations. Nat Rev Immunol 2024; 24:161-177. [PMID: 37726402 DOI: 10.1038/s41577-023-00933-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2023] [Indexed: 09/21/2023]
Abstract
Anti-cytokine autoantibodies (ACAAs) are increasingly recognized as modulating disease severity in infection, inflammation and autoimmunity. By reducing or augmenting cytokine signalling pathways or by altering the half-life of cytokines in the circulation, ACAAs can be either pathogenic or disease ameliorating. The origins of ACAAs remain unclear. Here, we focus on the most common ACAAs in the context of disease groups with similar characteristics. We review the emerging genetic and environmental factors that are thought to drive their production. We also describe how the profiling of ACAAs should be considered for the early diagnosis, active monitoring, treatment or sub-phenotyping of diseases. Finally, we discuss how understanding the biology of naturally occurring ACAAs can guide therapeutic strategies.
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Affiliation(s)
- Aristine Cheng
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- Division of Infectious Diseases, Department of Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Steven M Holland
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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2
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Bachanová P, Cheyne A, Broderick C, Newton SM, Levin M, Kaforou M. Comparative transcriptomic analysis of whole blood mycobacterial growth assays and tuberculosis patients' blood RNA profiles. Sci Rep 2022; 12:17684. [PMID: 36271270 PMCID: PMC9587058 DOI: 10.1038/s41598-022-20409-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/13/2022] [Indexed: 01/18/2023] Open
Abstract
In vitro whole blood infection models are used for elucidating the immune response to Mycobacterium tuberculosis (Mtb). They exhibit commonalities but also differences, to the in vivo blood transcriptional response during natural human Mtb disease. Here, we present a description of concordant and discordant components of the immune response in blood, quantified through transcriptional profiling in an in vitro whole blood infection model compared to whole blood from patients with tuberculosis disease. We identified concordantly and discordantly expressed gene modules and performed in silico cell deconvolution. A high degree of concordance of gene expression between both adult and paediatric in vivo-in vitro tuberculosis infection was identified. Concordance in paediatric in vivo vs in vitro comparison is largely characterised by immune suppression, while in adults the comparison is marked by concordant immune activation, particularly that of inflammation, chemokine, and interferon signalling. Discordance between in vitro and in vivo increases over time and is driven by T-cell regulation and monocyte-related gene expression, likely due to apoptotic depletion of monocytes and increasing relative fraction of longer-lived cell types, such as T and B cells. Our approach facilitates a more informed use of the whole blood in vitro model, while also accounting for its limitations.
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Affiliation(s)
- Petra Bachanová
- Department of Infectious Disease, Imperial College London, London, UK
| | - Ashleigh Cheyne
- Department of Infectious Disease, Imperial College London, London, UK
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, UK
| | - Claire Broderick
- Department of Infectious Disease, Imperial College London, London, UK
| | - Sandra M Newton
- Department of Infectious Disease, Imperial College London, London, UK
- Centre for Paediatrics and Child Health, Imperial College London, London, UK
| | - Michael Levin
- Department of Infectious Disease, Imperial College London, London, UK
- Centre for Paediatrics and Child Health, Imperial College London, London, UK
| | - Myrsini Kaforou
- Department of Infectious Disease, Imperial College London, London, UK.
- Centre for Paediatrics and Child Health, Imperial College London, London, UK.
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3
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Anterasian C, Warr AJ, Lacourse SM, Kinuthia J, Richardson BA, Nguyen FK, Matemo D, Maleche-Obimbo E, Stewart GCJ, Hawn TR. Non-IFNγ Whole Blood Cytokine Responses to Mycobacterium tuberculosis Antigens in HIV-exposed Infants. Pediatr Infect Dis J 2021; 40:922-929. [PMID: 34525006 PMCID: PMC8443847 DOI: 10.1097/inf.0000000000003254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND HIV-exposed uninfected (HEU) infants have increased risk of tuberculosis (TB). Testing for Mycobacterium tuberculosis (Mtb) infection is limited by reduced Quantiferon (QFT) sensitivity in infants and tuberculin skin test (TST) cross-reactivity with Bacillus Calmette-Guérin vaccine. Our objective is to assess if non-IFNγ cytokine responses to Mtb-specific antigens have improved sensitivity in detecting Mtb infection in HEU infants compared with QFT. METHODS HEU infants were enrolled in a randomized clinical trial of isoniazid preventive therapy (IPT) to prevent Mtb infection in Kenya (N = 300) and assessed at 12 months postrandomization (14 months of age) by TST and QFT-Plus. Non-IFNγ cytokine secretion (IL2, TNF, IP10, N = 229) in QFT-Plus supernatants was measured using Luminex assay. Logistic regression was used to assess the effect of IPT on Mtb infection outcomes in HEU infants. RESULTS Three of 251 (1.2%) infants were QFT-Plus positive. Non-IFNγ Mtb antigen-specific responses were detected in 12 additional infants (12/229, 5.2%), all TST negative. IPT was not associated with Mtb infection defined as any Mtb antigen-specific cytokine response (odds ratio = 0.7, P = 0.54). Mtb antigen-specific IL2/IP10 responses had fair correlation (τ = 0.25). Otherwise, non-IFNγ cytokine responses had minimal correlation with QFT-Plus and no correlation with TST size. CONCLUSIONS We detected non-IFNg Mtb antigen-specific T-cell responses in 14-month HEU infants. Non-IFNg cytokines may be more sensitive than IFNg in detecting infant Mtb infection. IPT during the first year of life was not associated with Mtb infection measured by IFNg, IL2, IP10 and TNF Mtb-specific responses.
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Affiliation(s)
| | - Alex J. Warr
- Department of Medicine, University of Washington, Seattle 98109, USA
| | - Sylvia M. Lacourse
- Department of Medicine, University of Washington, Seattle 98109, USA
- Department of Global Health, University of Washington, Seattle 98109, USA
| | - John Kinuthia
- Department of Research and Programs, Kenyatta National Hospital, Nairobi, Kenya
| | - Barbra A. Richardson
- Department of Global Health, University of Washington, Seattle 98109, USA
- Department of Biostatistics, University of Washington, Seattle 98109, USA
| | - Felicia K. Nguyen
- Department of Medicine, University of Washington, Seattle 98109, USA
| | - Daniel Matemo
- Department of Research and Programs, Kenyatta National Hospital, Nairobi, Kenya
| | | | | | - Thomas R. Hawn
- Department of Medicine, University of Washington, Seattle 98109, USA
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4
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Bok J, Hofland RW, Evans CA. Whole Blood Mycobacterial Growth Assays for Assessing Human Tuberculosis Susceptibility: A Systematic Review and Meta-Analysis. Front Immunol 2021; 12:641082. [PMID: 34046032 PMCID: PMC8144701 DOI: 10.3389/fimmu.2021.641082] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 03/08/2021] [Indexed: 01/20/2023] Open
Abstract
Background Whole blood mycobacterial growth assays (WBMGA) quantify mycobacterial growth in fresh blood samples and may have potential for assessing tuberculosis vaccines and identifying individuals at risk of tuberculosis. We evaluated the evidence for the underlying assumption that in vitro WBMGA results can predict in vivo tuberculosis susceptibility. Methods A systematic search was done for studies assessing associations between WBMGA results and tuberculosis susceptibility. Meta-analyses were performed for eligible studies by calculating population-weighted averages. Results No studies directly assessed whether WBMGA results predicted tuberculosis susceptibility. 15 studies assessed associations between WBMGA results and proven correlates of tuberculosis susceptibility, which we divided in two categories. Firstly, WBMGA associations with factors believed to reduce tuberculosis susceptibility were statistically significant in all eight studies of: BCG vaccination; vitamin D supplementation; altitude; and HIV-negativity/therapy. Secondly, WBMGA associations with probable correlates of tuberculosis susceptibility were statistically significant in three studies of tuberculosis disease, in a parasitism study and in two of the five studies of latent tuberculosis infection. Meta-analyses for associations between WBMGA results and BCG vaccination, tuberculosis infection, tuberculosis disease and HIV infection revealed consistent effects. There was considerable methodological heterogeneity. Conclusions The study results generally showed significant associations between WBMGA results and correlates of tuberculosis susceptibility. However, no study directly assessed whether WBMGA results predicted actual susceptibility to tuberculosis infection or disease. We recommend optimization and standardization of WBMGA methodology and prospective studies to determine whether WBMGA predict susceptibility to tuberculosis disease.
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Affiliation(s)
- Jeroen Bok
- Department of Infectious Disease, Imperial College London, London, United Kingdom.,Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Innovacion Por la Salud Y el Desarrollo (IPSYD), Asociación Benéfica PRISMA, Lima, Peru.,Department of Pulmonology and Tuberculosis, University Medical Center Utrecht, Utrecht, Netherlands
| | - Regina W Hofland
- Department of Pulmonology and Tuberculosis, University Medical Center Utrecht, Utrecht, Netherlands
| | - Carlton A Evans
- Department of Infectious Disease, Imperial College London, London, United Kingdom.,Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Innovacion Por la Salud Y el Desarrollo (IPSYD), Asociación Benéfica PRISMA, Lima, Peru
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5
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Grassi G, Vanini V, De Santis F, Romagnoli A, Aiello A, Casetti R, Cimini E, Bordoni V, Notari S, Cuzzi G, Mosti S, Gualano G, Palmieri F, Fraziano M, Goletti D, Agrati C, Sacchi A. PMN-MDSC Frequency Discriminates Active Versus Latent Tuberculosis and Could Play a Role in Counteracting the Immune-Mediated Lung Damage in Active Disease. Front Immunol 2021; 12:594376. [PMID: 33981297 PMCID: PMC8107479 DOI: 10.3389/fimmu.2021.594376] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 04/06/2021] [Indexed: 01/02/2023] Open
Abstract
Tuberculosis (TB), due to Mycobacterium tuberculosis infection, is still the principal cause of death caused by a single infectious agent. The balance between the bacillus and host defense mechanisms reflects the different manifestations of the pathology. Factors defining this variety are unclear and likely involve both mycobacterial and immunological components. Myeloid derived suppressor cells (MDSC) have been shown to be expanded during TB, but their role in human TB pathogenesis is not clear. We evaluated the frequency of circulating MDSC by flow-cytometry in 19 patients with active TB, 18 with latent TB infection (LTBI), and 12 healthy donors (HD) as control. Moreover, we investigated the capacity of MDSC to modulate the mycobactericidal activity of monocytes. The association between MDSC level and TB chest X-ray severity score was analyzed. We observed that, unlike active TB, polymorphonuclear (PMN)-MDSC are not expanded in LTBI patients, and, by performing a receiver operating characteristic (ROC) curve analysis, we found that PMN-MDSC frequency supported the discrimination between active disease and LTBI. Interestingly, we observed an association between PMN-MDSC levels and the severity of TB disease evaluated by chest X-ray. Specifically, PMN-MDSC frequency was higher in those classified with a low/mild severity score compared to those classified with a high severity score. Moreover, PMN-MDSC can impact mycobacterial growth by inducing ROS production in Bacillus Calmette et Guerin (BCG)-infected monocytes. This effect was lost when tested with M. tuberculosis (MTB), In conclusion, our data indicate that the elevated frequency of PMN-MDSC in IGRA-positive individuals is associated with active TB. Our findings also pointed out a beneficial role of PMN-MDSC during human active TB, most likely associated with the limitation of inflammation-induced tissue damage.
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Affiliation(s)
- Germana Grassi
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Valentina Vanini
- Laboratory of Translational Research, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy.,UOS Professioni Sanitarie Tecniche National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Rome, Italy
| | | | - Alessandra Romagnoli
- Department of Epidemiology, Preclinical Research, and Advanced Diagnostics, National Institute for Infectious Diseases 'Lazzaro Spallanzani'-IRCCS, Rome, Italy
| | - Alessandra Aiello
- Laboratory of Translational Research, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Rita Casetti
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Eleonora Cimini
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Veronica Bordoni
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Stefania Notari
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Gilda Cuzzi
- Laboratory of Translational Research, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Silvia Mosti
- Respiratory Infectious Diseases Unit, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Gina Gualano
- Respiratory Infectious Diseases Unit, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Fabrizio Palmieri
- Respiratory Infectious Diseases Unit, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Maurizio Fraziano
- Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Delia Goletti
- Laboratory of Translational Research, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Chiara Agrati
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
| | - Alessandra Sacchi
- Laboratory of Cellular Immunology and Pharmacology, National Institute for infectious Diseases "Lazzaro Spallanzani"-IRCCS, Rome, Italy
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6
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Basu Roy R, Sambou B, Sissoko M, Holder B, Gomez MP, Egere U, Sillah AK, Koukounari A, Kampmann B. Protection against mycobacterial infection: A case-control study of mycobacterial immune responses in pairs of Gambian children with discordant infection status despite matched TB exposure. EBioMedicine 2020; 59:102891. [PMID: 32675024 PMCID: PMC7502674 DOI: 10.1016/j.ebiom.2020.102891] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Children are particularly susceptible to tuberculosis. However, most children exposed to Mycobacterium tuberculosis are able to control the pathogen without evidence of infection. Correlates of human protective immunity against tuberculosis infection are lacking, and their identification would aid vaccine design. METHODS We recruited pairs of asymptomatic children with discordant tuberculin skin test status but the same sleeping proximity to the same adult with sputum smear-positive tuberculosis in a matched case-control study in The Gambia. Participants were classified as either Highly TB-Exposed Uninfected or Highly TB-Exposed Infected children. Serial luminescence measurements using an in vitro functional auto-luminescent Bacillus Calmette-Guérin (BCG) whole blood assay quantified the dynamics of host control of mycobacterial growth. Assay supernatants were analysed with a multiplex cytokine assay to measure associated inflammatory responses. FINDINGS 29 pairs of matched Highly TB-Exposed Uninfected and Highly TB-Exposed Infected children aged 5 to 15 years old were enroled. Samples from Highly TB-Exposed Uninfected children had higher levels of mycobacterial luminescence at 96 hours than Highly TB-Exposed Infected children. Highly TB-Exposed Uninfected children also produced less BCG-specific interferon-γ than Highly TB-Exposed Infected children at 24 hours and at 96 hours. INTERPRETATION Highly TB-Exposed Uninfected children showed less control of mycobacterial growth compared to Highly TB-Exposed Infected children in a functional assay, whilst cytokine responses mirrored infection status. FUNDING Clinical Research Training Fellowship funded under UK Medical Research Council/Department for International Development Concordat agreement and part of EDCTP2 programme supported by European Union (MR/K023446/1). Also MRC Program Grants (MR/K007602/1, MR/K011944/1, MC_UP_A900/1122).
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Affiliation(s)
- Robindra Basu Roy
- Department of Academic Paediatrics, Section of Paediatric Infectious Disease, Imperial College London, St. Mary's Hospital, Praed Street, London W2 1NY, United Kingdom; Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia; Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Basil Sambou
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Muhamed Sissoko
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Beth Holder
- Department of Academic Paediatrics, Section of Paediatric Infectious Disease, Imperial College London, St. Mary's Hospital, Praed Street, London W2 1NY, United Kingdom; Institute of Reproductive and Developmental Biology, Department of Metabolism, Digestion & Reproduction, Imperial College London, Du Cane Road, W12 0HS, United Kingdom
| | - Marie P Gomez
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Uzochukwu Egere
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia; Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place L3 5QA, United Kingdom
| | - Abdou K Sillah
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Artemis Koukounari
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Beate Kampmann
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia; Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom; The Vaccine Centre, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
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7
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Tanner R, Satti I, Harris SA, O'Shea MK, Cizmeci D, O'Connor D, Chomka A, Matsumiya M, Wittenberg R, Minassian AM, Meyer J, Fletcher HA, McShane H. Tools for Assessing the Protective Efficacy of TB Vaccines in Humans: in vitro Mycobacterial Growth Inhibition Predicts Outcome of in vivo Mycobacterial Infection. Front Immunol 2020; 10:2983. [PMID: 31998295 PMCID: PMC6968127 DOI: 10.3389/fimmu.2019.02983] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 12/05/2019] [Indexed: 12/16/2022] Open
Abstract
Tuberculosis (TB) remains a leading global cause of morbidity and mortality and an effective new vaccine is urgently needed. A major barrier to the rational development of novel TB vaccines is the lack of a validated immune correlate or biomarker of protection. Mycobacterial Growth Inhibition Assays (MGIAs) provide an unbiased measure of ability to control mycobacterial growth in vitro, and may represent a functional correlate of protection. However, the biological relevance of any potential correlate can only be assessed by determining the association with in vivo protection from either a controlled mycobacterial infection or natural development of TB disease. Our data demonstrate that the direct MGIA using peripheral blood mononuclear cells (PBMC) is measuring a biologically relevant response that correlates with protection from in vivo human BCG infection across two independent cohorts. This is the first report of an MGIA correlating with in vivo protection in the species-of-interest, humans, and furthermore on a per-individual as well as per-group basis. Control of mycobacterial growth in the MGIA is associated with a range of immune parameters measured post-BCG infection in vivo including the IFN-γ ELISpot response, frequency of PPD-specific IFN-γ or TNF-α producing CD4+ T cells and frequency of specific sub-populations of polyfunctional CD4+ T cells. Distinct transcriptomic profiles are associated with good vs. poor mycobacterial control in the MGIA, with good controllers showing enrichment for gene sets associated with antigen processing/presentation and the IL-23 pathway, and poor controllers showing enrichment for hypoxia-related pathways. This study represents an important step toward biologically validating the direct PBMC MGIA for use in TB vaccine development and furthermore demonstrates the utility of this assay in determining relevant immune mechanisms and pathways of protection.
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Affiliation(s)
- Rachel Tanner
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Iman Satti
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stephanie A. Harris
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Matthew K. O'Shea
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, The University of Birmingham, Birmingham, United Kingdom
| | - Deniz Cizmeci
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Daniel O'Connor
- Department of Paediatrics, University of Oxford, Oxford, United Kingdom
| | - Agnieszka Chomka
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Magali Matsumiya
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Rachel Wittenberg
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Angela M. Minassian
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Joel Meyer
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Helen A. Fletcher
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Helen McShane
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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8
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Asai M, Li Y, Khara JS, Robertson BD, Langford PR, Newton SM. Galleria mellonella: An Infection Model for Screening Compounds Against the Mycobacterium tuberculosis Complex. Front Microbiol 2019; 10:2630. [PMID: 31824448 PMCID: PMC6882372 DOI: 10.3389/fmicb.2019.02630] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/29/2019] [Indexed: 01/08/2023] Open
Abstract
Drug screening models have a vital role in the development of novel antimycobacterial agents which are urgently needed to tackle drug-resistant tuberculosis (TB). We recently established the larvae of the insect Galleria mellonella (greater wax moth) as a novel infection model for the Mycobacterium tuberculosis complex. Here we demonstrate its use as a rapid and reproducible screen to evaluate antimycobacterial drug efficacy using larvae infected with bioluminescent Mycobacterium bovis BCG lux. Treatment improved larval survival outcome and, with the exception of pyrazinamide, was associated with a significant reduction in in vivo mycobacterial bioluminescence over a 96 h period compared to the untreated controls. Isoniazid and rifampicin displayed the greatest in vivo efficacy and survival outcome. Thus G. mellonella, infected with bioluminescent mycobacteria, can rapidly determine in vivo drug efficacy, and has the potential to significantly reduce and/or replace the number of animals used in TB research.
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Affiliation(s)
- Masanori Asai
- Section of Paediatric Infectious Diseases, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Yanwen Li
- Department of Pharmacy, National University of Singapore, Singapore, Singapore
| | - Jasmeet Singh Khara
- Section of Paediatric Infectious Diseases, Department of Infectious Disease, Imperial College London, London, United Kingdom.,Department of Pharmacy, National University of Singapore, Singapore, Singapore
| | - Brian D Robertson
- MRC Centre for Molecular Bacteriology and Infection, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Paul R Langford
- Section of Paediatric Infectious Diseases, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Sandra M Newton
- Section of Paediatric Infectious Diseases, Department of Infectious Disease, Imperial College London, London, United Kingdom
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9
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Prabowo SA, Smith SG, Seifert K, Fletcher HA. Impact of individual-level factors on Ex vivo mycobacterial growth inhibition: Associations of immune cell phenotype, cytomegalovirus-specific response and sex with immunity following BCG vaccination in humans. Tuberculosis (Edinb) 2019; 119:101876. [PMID: 31698310 DOI: 10.1016/j.tube.2019.101876] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 08/02/2019] [Accepted: 09/29/2019] [Indexed: 01/18/2023]
Abstract
Understanding factors associated with varying efficacy of Bacillus Calmette-Guérin (BCG) would aid the development of improved vaccines against tuberculosis (TB). In addition, investigation of individual-level factors affecting mycobacterial-specific immune responses could provide insight into confounders of vaccine efficacy in clinical trials. Mycobacterial growth inhibition assays (MGIA) have been developed to assess vaccine immunogenicity ex vivo and provide a measure of immune function against live mycobacteria. In this study, we assessed the impact of immune cell phenotype, cytomegalovirus (CMV)-specific response and sex on ex vivo growth inhibition following historical BCG vaccination in a cohort of healthy individuals (n = 100). A higher frequency of cytokine-producing NK cells in peripheral blood was associated with enhanced ex vivo mycobacterial growth inhibition following historical BCG vaccination. A CMV-specific response was associated with T-cell activation, a risk factor for TB disease and we also observed an association between T-cell activation and ex vivo mycobacterial growth. Interestingly, BCG-vaccinated females in our cohort controlled mycobacterial growth better than males. In summary, our present study has shown that individual-level factors influence capacity to control mycobacterial growth following BCG vaccination and the MGIA could be used as a tool to assess how vaccine candidates may perform in different populations.
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Affiliation(s)
- Satria A Prabowo
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK; Tuberculosis Centre, London School of Hygiene and Tropical Medicine, London, UK.
| | - Steven G Smith
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK; Tuberculosis Centre, London School of Hygiene and Tropical Medicine, London, UK
| | - Karin Seifert
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Helen A Fletcher
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK; Tuberculosis Centre, London School of Hygiene and Tropical Medicine, London, UK
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10
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The evolving research agenda for paediatric tuberculosis infection. THE LANCET. INFECTIOUS DISEASES 2019; 19:e322-e329. [PMID: 31221543 DOI: 10.1016/s1473-3099(18)30787-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 10/19/2018] [Accepted: 12/11/2018] [Indexed: 12/30/2022]
Abstract
Following exposure to tuberculosis and subsequent infection, children often progress to tuberculosis disease more rapidly than adults. And yet the natural history of tuberculosis in children, as a continuum from exposure to infection and then to disease, is poorly understood. Children are rarely diagnosed with tuberculosis infection in routine care in international settings and few receive tuberculosis infection treatment. In this Personal View, we review the most up-to-date knowledge in three areas of childhood tuberculosis infection-namely, pathophysiology, diagnosis, and treatment. We then outline what is missing in each of these three areas to generate a priority research agenda. Finally, we suggest potential study designs that might answer these questions. Understanding of pathophysiology could be improved through animal models, laboratory studies assessing the immunological responses of blood or respiratory samples to Mycobacterium spp in vitro, as well as investigating immune responses in children exposed to tuberculosis. Identification of children with sub-clinical disease and at high risk of progression to clinically overt disease, would allow treatment to be targeted at those most likely to benefit. Optimisation and discovery of novel treatments for tuberculosis infection in children should account for mechanisms of action of tuberculosis drugs, as well as child-specific factors including pharmacokinetics and appropriate formulations. To conduct these studies, a change in mindset is required, with a recognition that the diagnosis and treatment of tuberculosis infection in children is a necessary component in addressing the overall tuberculosis epidemic. Collaboration between stakeholders will be required and funding will need to increase, both for research and implementation. The consequences of inaction, however, will lead to further decades of children suffering from what should increasingly be recognised as a preventable disease.
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11
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Lee H, Kim J, Kang YA, Kim DR, Sim B, Zelmer A, Fletcher HA, Dockrell HM, Smith SG, Cho SN. In vitro Mycobacterial Growth Inhibition in South Korean Adults With Latent TB Infection. Front Immunol 2019; 10:896. [PMID: 31105706 PMCID: PMC6497970 DOI: 10.3389/fimmu.2019.00896] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 04/08/2019] [Indexed: 01/24/2023] Open
Abstract
Background: It is important to understand the ability to inhibit mycobacterial growth in healthy adults who would have been Bacillus Calmette-Guérin (BCG) vaccinated in childhood as this group will be the potential target population for novel booster TB vaccine trials. In this study we investigated not only the long-term immunity induced by childhood BCG vaccination but also protective immunity in terms of the ability to inhibit mycobacterial growth in those who were BCG vaccinated in childhood, with evidence of recent or remote TB infection. Methods: We measured the baseline immune response using a functional mycobacterial growth inhibition assay (MGIA) as a novel approach and an intracellular cytokine staining (ICS) assay as a reference approach in healthy adults, with different status of Mycobacterium tuberculosis (Mtb) infection. Results: Based on MGIA responses in historically BCG-vaccinated healthy adults, demographical characteristics including age, and gender did not affect mycobacterial growth inhibition in PBMC. However, the uninfected healthy control (HC) group showed a greater ability to inhibit mycobacterial growth compared with the latent TB infection (LTBI) group (P = 0.0005). In terms of the M. tuberculosis antigen-specific T-cell immune response in diluted whole blood quantitated using an ICS assay, the LTBI group had a higher frequency of polyfunctional CD 4+ T cells compared with the HC group (P = 0.0002), although there was no correlation between ICS and the MGIA assay. Conclusion: The Mtb infection status had a significant impact on mycobacterial growth inhibition in PBMC from healthy adults in South Korea, a country with an intermediate burden of tuberculosis, with healthy controls showing the greatest mycobacterial growth inhibition.
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Affiliation(s)
- Hyejon Lee
- Clinical Vaccine Research Section, International Tuberculosis Research Center, Seoul, South Korea
- Department of Microbiology, Institute of Immunology and Immunological Disease, Yonsei University College of Medicine, Seoul, South Korea
| | - Jungho Kim
- Clinical Vaccine Research Section, International Tuberculosis Research Center, Seoul, South Korea
- Department of Microbiology, Institute of Immunology and Immunological Disease, Yonsei University College of Medicine, Seoul, South Korea
| | - Young Ae Kang
- Division of Pulmonary, Department of Internal Medicine, Severance Hospital, Institute of Chest Diseases, Yonsei University College of Medicine, Seoul, South Korea
| | - Deok Ryun Kim
- Development and Delivery Unit, International Vaccine Institute, Seoul, South Korea
| | - Bora Sim
- Department of Microbiology, Institute of Immunology and Immunological Disease, Yonsei University College of Medicine, Seoul, South Korea
| | - Andrea Zelmer
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Helen A. Fletcher
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Hazel M. Dockrell
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Steven G. Smith
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sang-Nae Cho
- Clinical Vaccine Research Section, International Tuberculosis Research Center, Seoul, South Korea
- Department of Microbiology, Institute of Immunology and Immunological Disease, Yonsei University College of Medicine, Seoul, South Korea
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12
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De Santis F, Poerio N, Gismondi A, Nanni V, Di Marco G, Nisini R, Thaller MC, Canini A, Fraziano M. Hydroalcoholic extract from Origanum vulgare induces a combined anti-mycobacterial and anti-inflammatory response in innate immune cells. PLoS One 2019; 14:e0213150. [PMID: 30830942 PMCID: PMC6398838 DOI: 10.1371/journal.pone.0213150] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/17/2019] [Indexed: 01/25/2023] Open
Abstract
In nature, many plants or their extracted compounds have been found to possess anti-inflammatory features and therapeutic properties against infectious as well as non-infectious diseases, including cancer. In this study, we analysed the immunomodulatory effects on innate immune cells of hydroalcoholic extract from Origanum vulgare L. ssp. hirtum (HyE-Ov), a plant traditionally known for its anti-oxidative properties. The effects of HyE-Ov were tested on human monocyte derived dendritic cells (DC), type-1 (M1) and type-2 macrophages (M2) infected with M. bovis Bacille Calmette-Guérin (BCG), used as a model of persistent intracellular bacterium. DC, M1 and M2 treated with HyE-Ov significantly enhanced their mycobactericidal activity, which was associated with phagosomal acidification in M1 and M2 and increase of phagosomal, but not mitochondrial ROS production in M1, M2, and DC. Treatment of BCG-infected DC with HyE-Ov significantly reduced TNF-α and IL-12 production and increased TGF-β synthesis. Finally, experiments were repeated using eight different HPLC fractions of HyE-Ov. Results showed that the capability to activate anti-microbial and anti-inflammatory response is shared by different fractions, suggesting that diverse bioactive molecules are present within the hydroalcoholic extract. Altogether, these results show that HyE-Ov promotes anti-mycobacterial innate immunity and limits inflammatory response in vitro and suggest that this plant extract may be exploitable as phytocomplex or nutraceutical for novel host-directed therapeutic approaches.
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Affiliation(s)
| | - Noemi Poerio
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Angelo Gismondi
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Valentina Nanni
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Gabriele Di Marco
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Roberto Nisini
- Department of infectious diseases, Istituto Superiore di Sanità, Rome, Italy
| | | | - Antonella Canini
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Maurizio Fraziano
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
- * E-mail:
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13
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Optimisation, harmonisation and standardisation of the direct mycobacterial growth inhibition assay using cryopreserved human peripheral blood mononuclear cells. J Immunol Methods 2019; 469:1-10. [PMID: 30710562 PMCID: PMC7926177 DOI: 10.1016/j.jim.2019.01.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/13/2018] [Accepted: 01/15/2019] [Indexed: 11/21/2022]
Abstract
A major challenge to tuberculosis (TB) vaccine development is the lack of a validated immune correlate of protection. Mycobacterial growth inhibition assays (MGIAs) represent an unbiased measure of the ability to control mycobacterial growth in vitro. A successful MGIA could be applied to preclinical and clinical post-vaccination samples to aid in the selection of novel vaccine candidates at an early stage and provide a relevant measure of immunogenicity and protection. However, assay harmonisation is critical to ensure that comparable information can be extracted from different vaccine studies. As part of the FP7 European Research Infrastructures for Poverty Related Diseases (EURIPRED) consortium, we aimed to optimise the direct MGIA, assess repeatability and reproducibility, and harmonise the assay across different laboratories. We observed an improvement in repeatability with increased cell number and increased mycobacterial input. Furthermore, we determined that co-culturing in static 48-well plates compared with rotating 2 ml tubes resulted in a 23% increase in cell viability and a 500-fold increase in interferon-gamma (IFN-γ) production on average, as well as improved reproducibility between replicates, assay runs and sites. Applying the optimised conditions, we report repeatability to be <5% coefficient of variation (CV), intermediate precision to be <20% CV, and inter-site reproducibility to be <30% CV; levels within acceptable limits for a functional cell-based assay. Using relevant clinical samples, we demonstrated comparable results across two shared sample sets at three sites. Based on these findings, we have established a standardised operating procedure (SOP) for the use of the direct PBMC MGIA in TB vaccine development.
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14
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Basu Roy R, Sambou B, Uhía I, Roetynck S, Robertson BD, Kampmann B. An Auto-luminescent Fluorescent BCG Whole Blood Assay to Enable Evaluation of Paediatric Mycobacterial Responses Using Minimal Blood Volumes. Front Pediatr 2019; 7:151. [PMID: 31114771 PMCID: PMC6503113 DOI: 10.3389/fped.2019.00151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Accepted: 04/01/2019] [Indexed: 12/15/2022] Open
Abstract
Introduction: Understanding protective human immunity against mycobacteria is critical to developing and evaluating new vaccines against tuberculosis. Children are the most susceptible population to infection, disease, and death from tuberculosis, but also have the strongest evidence of BCG-inducible protection. Limited amounts of blood can be obtained for research purposes in paediatrics and therefore there is a need for high-yield, low-volume, human immunology assays. Methods: We transformed BCG Danish with plasmids encoding luciferase full operon derived from Photorhabdus luminescens together with Green Fluorescent Protein and antibiotic selection markers. We characterised the luminescent and fluorescent properties of this recombinant BCG strain (BCG-GFP-LuxFO) using a luminometer and flow cytometry and developed a paediatric whole blood in vitro infection model. Results: Luminescence of BCG-GFP-LuxFO correlated with optical density (Spearman Rank Correlation coefficient r = 0.985, p < 0.0001) and colony forming units (CFUs) in liquid culture medium (r = 0.971, p < 0.0001). Fluorescence of BCG-GFP-LuxFO in paediatric whole blood was confirmed by flow cytometry in granulocytes and monocytes 1 h following infection. Luminescence of BCG-GFP-LuxFO in whole blood corresponded with CFUs (r = 0.7123, p < 0.0001). Conclusion: The BCG-GFP-LuxFO assay requires 225 μL whole blood per sample, from which serial luminescence measurements can be obtained, together with biochemical analysis of supernatants and cellular assay applications using its fluorescent properties. This offers the opportunity to study human-mycobacterial interactions using multiple experimental modalities with only minimal blood volumes. It is therefore a valuable method for investigating paediatric immunity to tuberculosis.
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Affiliation(s)
- Robindra Basu Roy
- Department of Paediatrics, Centre for International Child Health, Imperial College London, London, United Kingdom.,Vaccines & Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine (LSHTM), Banjul, The Gambia
| | - Basil Sambou
- Vaccines & Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine (LSHTM), Banjul, The Gambia
| | - Iria Uhía
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Sophie Roetynck
- Vaccines & Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine (LSHTM), Banjul, The Gambia
| | - Brian D Robertson
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Beate Kampmann
- Department of Paediatrics, Centre for International Child Health, Imperial College London, London, United Kingdom.,Vaccines & Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine (LSHTM), Banjul, The Gambia.,Faculty of Infectious and Tropical Diseases, The Vaccine Centre, London School of Hygiene and Tropical Medicine, London, United Kingdom
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15
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Li Y, Spiropoulos J, Cooley W, Khara JS, Gladstone CA, Asai M, Bossé JT, Robertson BD, Newton SM, Langford PR. Galleria mellonella - a novel infection model for the Mycobacterium tuberculosis complex. Virulence 2018; 9:1126-1137. [PMID: 30067135 PMCID: PMC6086298 DOI: 10.1080/21505594.2018.1491255] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Animal models have long been used in tuberculosis research to understand disease pathogenesis and to evaluate novel vaccine candidates and anti-mycobacterial drugs. However, all have limitations and there is no single animal model which mimics all the aspects of mycobacterial pathogenesis seen in humans. Importantly mice, the most commonly used model, do not normally form granulomas, the hallmark of tuberculosis infection. Thus there is an urgent need for the development of new alternative in vivo models. The insect larvae, Galleria mellonella has been increasingly used as a successful, simple, widely available and cost-effective model to study microbial infections. Here we report for the first time that G. mellonella can be used as an infection model for members of the Mycobacterium tuberculosis complex. We demonstrate a dose-response for G. mellonella survival infected with different inocula of bioluminescent Mycobacterium bovis BCG lux, and demonstrate suppression of mycobacterial luminesence over 14 days. Histopathology staining and transmission electron microscopy of infected G. mellonella phagocytic haemocytes show internalization and aggregation of M. bovis BCG lux in granuloma-like structures, and increasing accumulation of lipid bodies within M. bovis BCG lux over time, characteristic of latent tuberculosis infection. Our results demonstrate that G. mellonella can act as a surrogate host to study the pathogenesis of mycobacterial infection and shed light on host-mycobacteria interactions, including latent tuberculosis infection.
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Affiliation(s)
- Yanwen Li
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK
| | - John Spiropoulos
- b Department of Pathology , Animal and Plant Health Agency , Addlestone , UK
| | - William Cooley
- b Department of Pathology , Animal and Plant Health Agency , Addlestone , UK
| | - Jasmeet Singh Khara
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK.,c Department of Pharmacy , National University of Singapore , Singapore
| | - Camilla A Gladstone
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK
| | - Masanori Asai
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK
| | - Janine T Bossé
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK
| | - Brian D Robertson
- d MRC Centre for Molecular Bacteriology and Infection, Department of Medicine , Imperial College London , London , UK
| | - Sandra M Newton
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK
| | - Paul R Langford
- a Section of Paediatric Infectious Diseases and Allergy, Department of Medicine , Imperial College London , London , UK
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16
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Lowe DM, Demaret J, Bangani N, Nakiwala JK, Goliath R, Wilkinson KA, Wilkinson RJ, Martineau AR. Differential Effect of Viable Versus Necrotic Neutrophils on Mycobacterium tuberculosis Growth and Cytokine Induction in Whole Blood. Front Immunol 2018; 9:903. [PMID: 29755473 PMCID: PMC5934482 DOI: 10.3389/fimmu.2018.00903] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/11/2018] [Indexed: 01/14/2023] Open
Abstract
Neutrophils exert both positive and negative influences on the host response to tuberculosis, but the mechanisms by which these differential effects are mediated are unknown. We studied the impact of live and dead neutrophils on the control of Mycobacterium tuberculosis using a whole blood bioluminescence-based assay, and assayed supernatant cytokine concentrations using Luminex™ technology and ELISA. CD15+ granulocyte depletion from blood prior to infection with M. tuberculosis-lux impaired control of mycobacteria by 96 h, with a greater effect than depletion of CD4+, CD8+, or CD14+ cells (p < 0.001). Augmentation of blood with viable granulocytes significantly improved control of mycobacteria by 96 h (p = 0.001), but augmentation with necrotic granulocytes had the opposite effect (p = 0.01). Both augmentations decreased supernatant concentrations of tumor necrosis factor and interleukin (IL)-12 p40/p70, but necrotic granulocyte augmentation also increased concentrations of IL-10, G-CSF, GM-CSF, and CCL2. Necrotic neutrophil augmentation reduced phagocytosis of FITC-labeled M. bovis BCG by all phagocytes, whereas viable neutrophil augmentation specifically reduced early uptake by CD14+ cells. The immunosuppressive effect of dead neutrophils required necrotic debris rather than supernatant. We conclude that viable neutrophils enhance control of M. tuberculosis in blood, but necrotic neutrophils have the opposite effect-the latter associated with induction of IL-10, growth factors, and chemoattractants. Our findings suggest a mechanism by which necrotic neutrophils may exert detrimental effects on the host response in active tuberculosis.
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Affiliation(s)
- David M Lowe
- Wellcome Centre for Infectious Diseases Research in Africa, Department of Medicine, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Imperial College London, London, United Kingdom.,Institute of Immunity and Transplantation, University College London, London, United Kingdom
| | - Julie Demaret
- Barts and The London School of Medicine, Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Nonzwakazi Bangani
- Wellcome Centre for Infectious Diseases Research in Africa, Department of Medicine, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Justine K Nakiwala
- Wellcome Centre for Infectious Diseases Research in Africa, Department of Medicine, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa.,Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Rene Goliath
- Wellcome Centre for Infectious Diseases Research in Africa, Department of Medicine, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Katalin A Wilkinson
- Wellcome Centre for Infectious Diseases Research in Africa, Department of Medicine, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa.,The Francis Crick Institute, London, United Kingdom
| | - Robert J Wilkinson
- Wellcome Centre for Infectious Diseases Research in Africa, Department of Medicine, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Imperial College London, London, United Kingdom.,The Francis Crick Institute, London, United Kingdom
| | - Adrian R Martineau
- Barts and The London School of Medicine, Blizard Institute, Queen Mary University of London, London, United Kingdom
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17
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Mycobacterium tuberculosis Exploits a Molecular Off Switch of the Immune System for Intracellular Survival. Sci Rep 2018; 8:661. [PMID: 29330469 PMCID: PMC5766484 DOI: 10.1038/s41598-017-18528-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 12/11/2017] [Indexed: 01/09/2023] Open
Abstract
Mycobacterium tuberculosis (M. tuberculosis) survives and multiplies inside human macrophages by subversion of immune mechanisms. Although these immune evasion strategies are well characterised functionally, the underlying molecular mechanisms are poorly understood. Here we show that during infection of human whole blood with M. tuberculosis, host gene transcriptional suppression, rather than activation, is the predominant response. Spatial, temporal and functional characterisation of repressed genes revealed their involvement in pathogen sensing and phagocytosis, degradation within the phagolysosome and antigen processing and presentation. To identify mechanisms underlying suppression of multiple immune genes we undertook epigenetic analyses. We identified significantly differentially expressed microRNAs with known targets in suppressed genes. In addition, after searching regions upstream of the start of transcription of suppressed genes for common sequence motifs, we discovered novel enriched composite sequence patterns, which corresponded to Alu repeat elements, transposable elements known to have wide ranging influences on gene expression. Our findings suggest that to survive within infected cells, mycobacteria exploit a complex immune “molecular off switch” controlled by both microRNAs and Alu regulatory elements.
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18
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Gupta-Wright A, Tembo D, Jambo KC, Chimbayo E, Mvaya L, Caldwell S, Russell DG, Mwandumba HC. Functional Analysis of Phagocyte Activity in Whole Blood from HIV/Tuberculosis-Infected Individuals Using a Novel Flow Cytometry-Based Assay. Front Immunol 2017; 8:1222. [PMID: 29033941 PMCID: PMC5624998 DOI: 10.3389/fimmu.2017.01222] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 09/15/2017] [Indexed: 12/02/2022] Open
Abstract
The accurate assessment of immune competence through ex vivo analysis is paramount to our understanding of those immune mechanisms that lead to protection or susceptibility against a broad range of human pathogens. We have developed a flow cytometry-based, whole blood phagocyte functional assay that utilizes the inflammatory inducer zymosan, coupled to OxyBURST-SE, a fluorescent reporter of phagosomal oxidase activity. The assay measures both phagocytic uptake and the superoxide burst in the phagocyte populations in whole blood. We utilized this assay to demonstrate impaired superoxide burst activity in the phagocytes of hospitalized HIV-positive patients with laboratory-confirmed tuberculosis. These data validate the use of the assay to assess the immune competence of patients in a clinical setting. The method is highly reproducible with minimal intraindividual variation and opens opportunities for the rapid assessment of cellular immune competence in peripheral blood in a disease setting.
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Affiliation(s)
- Ankur Gupta-Wright
- College of Medicine, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Clinical Research Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Dumizulu Tembo
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Kondwani C Jambo
- College of Medicine, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Elizabeth Chimbayo
- College of Medicine, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Leonard Mvaya
- College of Medicine, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Shannon Caldwell
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - David G Russell
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Henry C Mwandumba
- College of Medicine, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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19
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Application of a whole blood mycobacterial growth inhibition assay to study immunity against Mycobacterium tuberculosis in a high tuberculosis burden population. PLoS One 2017; 12:e0184563. [PMID: 28886145 PMCID: PMC5590973 DOI: 10.1371/journal.pone.0184563] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 08/25/2017] [Indexed: 11/19/2022] Open
Abstract
The determinants of immunological protection against Mycobacterium tuberculosis (M.tb) infection in humans are not known. Mycobacterial growth inhibition assays have potential utility as in vitro surrogates of in vivo immunological control of M.tb. We evaluated a whole blood growth inhibition assay in a setting with high burden of TB and aimed to identify immune responses that correlate with control of mycobacterial growth. We hypothesized that individuals with underlying M.tb infection will exhibit greater M.tb growth inhibition than uninfected individuals and that children aged 4 to 12 years, an age during which TB incidence is curiously low, will also exhibit greater M.tb growth inhibition than adolescents or adults. Neither M.tb infection status, age of the study participants, nor M.tb strain was associated with differential control of mycobacterial growth. Abundance and function of innate or T cell responses were also not associated with mycobacterial growth. Our data suggest that this assay does not provide a useful measure of age-associated differential host control of M.tb infection in a high TB burden setting. We propose that universally high levels of mycobacterial sensitization (through environmental non-tuberculous mycobacteria and/or universal BCG vaccination) in persons from high TB burden settings may impart broad inhibition of mycobacterial growth, irrespective of M.tb infection status. This sensitization may mask the augmentative effects of mycobacterial sensitization on M.tb growth inhibition that is typical in low burden settings.
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20
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Brennan MJ, Tanner R, Morris S, Scriba TJ, Achkar JM, Zelmer A, Hokey DA, Izzo A, Sharpe S, Williams A, Penn-Nicholson A, Erasmus M, Stylianou E, Hoft DF, McShane H, Fletcher HA. The Cross-Species Mycobacterial Growth Inhibition Assay (MGIA) Project, 2010-2014. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:e00142-17. [PMID: 28701467 PMCID: PMC5585695 DOI: 10.1128/cvi.00142-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The development of a functional biomarker assay in the tuberculosis (TB) field would be widely recognized as a major advance in efforts to develop and to test novel TB vaccine candidates efficiently. We present preliminary studies using mycobacterial growth inhibition assays (MGIAs) to detect Mycobacterium bovis BCG vaccine responses across species, and we extend this work to determine whether a standardized MGIA can be applied in characterizing new TB vaccines. The comparative MGIA studies reviewed here aimed to evaluate robustness, reproducibility, and ability to reflect in vivo responses. In doing so, they have laid the foundation for the development of a MGIA that can be standardized and potentially qualified. A major challenge ahead lies in better understanding the relationships between in vivo protection, in vitro growth inhibition, and the immune mechanisms involved. The final outcome would be a MGIA that could be used with confidence in TB vaccine trials. We summarize data arising from this project, present a strategy to meet the goals of developing a functional assay for TB vaccine testing, and describe some of the challenges encountered in performing and transferring such assays.
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Affiliation(s)
| | - Rachel Tanner
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Sheldon Morris
- Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland, USA
| | - Thomas J Scriba
- South African Tuberculosis Vaccine Initiative and Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Jacqueline M Achkar
- Departments of Medicine, Microbiology, and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Andrea Zelmer
- Department of Immunology and Infection, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Angelo Izzo
- Colorado State University, Fort Collins, Colorado, USA
| | - Sally Sharpe
- Public Health England, Porton Down, Salisbury, United Kingdom
| | - Ann Williams
- Public Health England, Porton Down, Salisbury, United Kingdom
| | - Adam Penn-Nicholson
- South African Tuberculosis Vaccine Initiative and Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Mzwandile Erasmus
- South African Tuberculosis Vaccine Initiative and Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Elena Stylianou
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | | | - Helen McShane
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Helen A Fletcher
- Department of Immunology and Infection, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Oliveira TL, Rizzi C, Dellagostin OA. Recombinant BCG vaccines: molecular features and their influence in the expression of foreign genes. Appl Microbiol Biotechnol 2017; 101:6865-6877. [PMID: 28779291 DOI: 10.1007/s00253-017-8439-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/13/2017] [Accepted: 07/15/2017] [Indexed: 01/17/2023]
Abstract
Recombinant Mycobacterium bovis BCG vaccines (rBCG) were first developed in the 1990s as a means of expressing antigens from multiple pathogens. This review examines the key structural factors of recombinant M. bovis that influence the expression of the heterologous antigens and the generation of genetic and functional stability in rBCG, which are crucial for inducing strong and lasting immune responses. The fundamental aim of this paper is to provide an overview of factors that affect the expression of recombinant proteins in BCG and the generation of the immune response against the target antigens, including mycobacterial promoters, location of foreign antigens, and stability of the vectors. The reporter systems that have been employed for evaluation of these molecular features in BCG are also reviewed here.
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Affiliation(s)
- Thaís Larré Oliveira
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Caroline Rizzi
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Odir Antônio Dellagostin
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil. .,Unidade de Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário, Caixa Postal 354, Pelotas, RS, CEP 96010-900, Brazil.
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A novel mycobacterial In Vitro infection assay identifies differences of induced macrophage apoptosis between CD4+ and CD8+ T cells. PLoS One 2017; 12:e0171817. [PMID: 28199374 PMCID: PMC5310865 DOI: 10.1371/journal.pone.0171817] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 01/26/2017] [Indexed: 12/03/2022] Open
Abstract
Macrophages are natural host cells for pathogenic mycobacteria, like Mycobacterium tuberculosis (M.tb). Immune surveillance by T cells and interaction with M.tb infected macrophages is crucial for protection against M.tb reactivation and development of active tuberculosis. Several factors play a role in the control of M.tb infection but reliable biomarkers remain elusive. One major obstacle is the absence of functional in vitro assays which allow concomitant determination of i) mycobacterial eradication; ii) cytotoxic effects on host macrophages; and iii) effector T-cell functions. We established a novel functional in vitro assay based on flow cytometry analysis of monocyte-derived macrophages (MDM) infected with a Mycobacterium bovis BCG strain containing a tetracycline inducible live/dead reporter plasmid (LD-BCG). MDM of healthy human donors were generated in vitro and infected with defined LD-BCG numbers. After short-term MDM/LD-BCG co-incubation with autologous effector T cells or in the presence of antibiotics, proportions of MDM containing live or dead LD-BCG were determined by flow cytometry. Concomitant measure of defined numbers of added beads allowed comparison of absolute MDM numbers between samples. Differential effects of T-cell subpopulations on anti-mycobacterial cytotoxicity and on MDM apoptosis were determined. Flow cytometry measure of MDM/LD-BCG treated with rifampicin correlated well with mycobacterial colony forming units and fluorescence microscopy results. Co-culture with pre-activated effector T cells reduced viability of both, LD-BCG and MDM, in a concentration-dependent manner. M.tb protein specific CD4+ and CD8+ T-cells contributed similarly to anti-mycobacterial cytotoxicity but CD4+ T cells induced higher levels of apoptosis in infected MDMs. This novel assay enables rapid quantification of anti-mycobacterial cytotoxicity and characterization of effector functions. Our functional in vitro assay has the potential to contribute to the identification of biomarkers for protective T-cell responses against tuberculosis.
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Abstract
New and effective tuberculosis (TB) vaccines are urgently needed to control pulmonary TB, and in particular to prevent the spread of drug-resistant strains of Mycobacterium tuberculosis. These drug-resistant strains can range from those resistant to first-line drugs to those that are almost impossible to treat. To develop new and effective vaccines for HIV and malaria has been difficult and it is proving to be just as challenging for TB. TB is a complicated disease with a spectrum from apparently controlled latent infection to active clinical disease and so different types of preventive or post-exposure vaccine may be needed. Identifying the most promising vaccine candidates to move into clinical trials is difficult, as we lack biomarker signatures that can predict protective efficacy. There is a risk that the failure of the MVA-85A vaccine to show efficacy when given to previously BCG-vaccinated South African infants will impact on the resources available for the development and trials of other candidate TB vaccines. Continued support for the development of new TB vaccines should remain a priority as an effective vaccine would bring huge public health benefits.
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Polyfunctional CD4 T-cells correlate with in vitro mycobacterial growth inhibition following Mycobacterium bovis BCG-vaccination of infants. Vaccine 2016; 34:5298-5305. [PMID: 27622301 DOI: 10.1016/j.vaccine.2016.09.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/15/2016] [Accepted: 09/02/2016] [Indexed: 01/02/2023]
Abstract
BACKGROUND Vaccination with Bacillus Calmette Guerin (BCG) protects infants against childhood tuberculosis however the immune mechanisms involved are not well understood. Further elucidation of the infant immune response to BCG will aid with the identification of immune correlates of protection against tuberculosis and with the design of new improved vaccines. The purpose of this study was to investigate BCG-induced CD4+ T-cell responses in blood samples from infants for cytokine secretion profiles thought to be important for protection against tuberculosis and compare these to PBMC-mediated in vitro mycobacterial growth inhibition. METHODS Blood from BCG-vaccinated or unvaccinated infants was stimulated overnight with Mycobacterium tuberculosis (M. tb) purified protein derivative (PPD) or controls and intracellular cytokine staining and flow cytometry used to measure CD4+T-cell responses. PBMC cryopreserved at the time of sample collection were thawed and incubated with live BCG for four days following which inhibition of BCG growth was determined. RESULTS PPD-specific IFNγ+TNFα+IL-2+CD4+T-cells represented the dominant T-cell response at 4monthsand1yearafter infant BCG. These responses were undetectable in age-matched unvaccinated infants. IL-17+CD4+T-cells were significantly more frequent in vaccinated infants at 4monthsbut not at 1-year post-BCG. PBMC-mediated inhibition of mycobacterial growth was significantly enhanced at 4monthspost-BCG as compared to unvaccinated controls. In an analysis of all samples with both datasets available, mycobacterial growth inhibition correlated significantly with the frequency of polyfunctional (IFNγ+TNFα+IL-2+) CD4+T-cells. CONCLUSIONS These data suggest that BCG vaccination of infants induces specific polyfunctional T-helper-1 and T-helper-17 responses and the ability, in the PBMC compartment, to inhibit the growth of mycobacteria in vitro. We also demonstrate that polyfunctional T-helper-1 cells may play a role in growth inhibition as evidenced by a significant correlation between the two.
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Effect of Antiretroviral Therapy on HIV-mediated Impairment of the Neutrophil Antimycobacterial Response. Ann Am Thorac Soc 2016; 12:1627-37. [PMID: 26368270 DOI: 10.1513/annalsats.201507-463oc] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RATIONALE Experimental and epidemiological evidence suggests that neutrophils are important in the host response to tuberculosis. HIV infection, which increases the risk of tuberculosis, adversely affects neutrophil function. OBJECTIVES To determine the impact of HIV and antiretroviral therapy on neutrophil antimycobacterial activity. METHODS We performed a cross-sectional comparison of neutrophil functions in 20 antiretroviral-naive HIV-infected and 20 HIV-uninfected individuals using luminescence-, flow cytometry-, and ELISA-based assays. We then conducted a prospective study in the HIV-infected individuals investigating these parameters during the first 6 months of antiretroviral therapy. Surface markers of neutrophil activation were investigated in a separate cohort using flow cytometry. MEASUREMENTS AND MAIN RESULTS HIV infection impaired control of Mycobacterium tuberculosis by neutrophils (mean ratio of mycobacterial luminescence in neutrophil samples vs. serum controls at 1 hour in HIV-infected participants, 0.88 ± 0.13 vs. HIV-uninfected participants, 0.76 ± 0.14; P = 0.01; at 24 hours, 0.82 ± 0.13 vs. 0.71 ± 0.13; P = 0.01). The extent of impairment correlated with log[HIV viral load]. Neutrophil cell death after 24 hours' incubation with M. tuberculosis was higher in the HIV-infected cohort (85.3 ± 11.8% vs. 57.9 ± 22.4% necrotic cells; P < 0.0001). Neutrophils from HIV-infected participants demonstrated significantly more CD62L-negative cells (median, 23.0 vs. 8.5%; P = 0.008) and CD16-negative cells (3.2 vs. 1.3%, P = 0.03). Antiretroviral therapy restored mycobacterial restriction and pattern of neutrophil death toward levels seen in HIV-uninfected persons. CONCLUSIONS Neutrophils in antiretroviral-naive HIV-infected persons are hyperactivated, eliminate M. tuberculosis less effectively than in HIV-uninfected individuals, and progress rapidly to necrotic cell death. These factors are ameliorated by antiretroviral therapy.
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López-Medrano R, Guerra-Laso JM, López-Fidalgo E, Diez-Tascón C, García-García S, Blanco-Conde S, Rivero-Lezcano OM. Plasma contributes to the antimicrobial activity of whole blood against Mycobacterium tuberculosis. Innate Immun 2016; 22:557-66. [PMID: 27554054 DOI: 10.1177/1753425916663311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 06/29/2016] [Indexed: 11/16/2022] Open
Abstract
The whole blood model for infection has proven useful to analyze the immunological response to Mycobacterium tuberculosis, because it exerts a significant antimicrobial activity. Although this activity has been generally assumed to be cellular, we have found that the leukocyte fraction of blood from healthy volunteers did not kill the bacilli. We have discovered that plasma was responsible for a large proportion, but not all, of the antimicrobial activity. Furthermore, infected monocytes controlled the mycobacterial multiplication when cultivated in the presence of plasma. Intriguingly, serum from the same donors did not share this activity, although it was able to eliminate the non-pathogenic Mycobacterium gordonae To identify the remaining components that participate in the antimycobacterial activity we fractionated blood in leukocytes, plasma, erythrocytes and platelets, and analyzed the bactericidal power of each fraction and their combinations using a factorial design. We found that erythrocytes, but not platelets, participated and showed by flow cytometry that mycobacteria physically associated with erythrocytes. We propose that in exposed healthy individuals that show 'early clearance' of the mycobacteria, the innate response is predominantly humoral, probably through the effect of antimicrobial peptides and proteins.
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Affiliation(s)
| | - José Manuel Guerra-Laso
- Servicio de Medicina Interna, Complejo Asistencial Universitario de León, (CAULE), León, Spain
| | - Eduardo López-Fidalgo
- Unidad de Investigación, Complejo Asistencial Universitario de León (CAULE), León, Spain
| | - Cristina Diez-Tascón
- Servicio de Anatomía Patológica, Complejo Asistencial Universitario de León (CAULE), León, Spain Institute of Biomedicine (IBIOMED), Universidad de León, León, Spain
| | - Silvia García-García
- Servicio de Neumología, Complejo Asistencial Universitario de León (CAULE), León, Spain
| | - Sara Blanco-Conde
- Servicio de Análisis Clínicos, Complejo Asistencial Universitario de León (CAULE), León, Spain
| | - Octavio Miguel Rivero-Lezcano
- Unidad de Investigación, Complejo Asistencial Universitario de León (CAULE), León, Spain Institute of Biomedicine (IBIOMED), Universidad de León, León, Spain Fundación Instituto de Estudios de Ciencias de la Salud de Castilla y León (IECSCYL), León, Spain
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Tanner R, O'Shea MK, Fletcher HA, McShane H. In vitro mycobacterial growth inhibition assays: A tool for the assessment of protective immunity and evaluation of tuberculosis vaccine efficacy. Vaccine 2016; 34:4656-4665. [PMID: 27527814 DOI: 10.1016/j.vaccine.2016.07.058] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 06/07/2016] [Accepted: 07/29/2016] [Indexed: 01/28/2023]
Abstract
Tuberculosis (TB) continues to pose a serious global health threat, and the current vaccine, BCG, has variable efficacy. However, the development of a more effective vaccine is severely hampered by the lack of an immune correlate of protection. Candidate vaccines are currently evaluated using preclinical animal models, but experiments are long and costly and it is unclear whether the outcomes are predictive of efficacy in humans. Unlike measurements of single immunological parameters, mycobacterial growth inhibition assays (MGIAs) represent an unbiased functional approach which takes into account a range of immune mechanisms and their complex interactions. Such a controlled system offers the potential to evaluate vaccine efficacy and study mediators of protective immunity against Mycobacterium tuberculosis (M.tb). This review discusses the underlying principles and relative merits and limitations of the different published MGIAs, their demonstrated abilities to measure mycobacterial growth inhibition and vaccine efficacy, and what has been learned about the immune mechanisms involved.
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Affiliation(s)
- Rachel Tanner
- The Jenner Institute, University of Oxford, Oxford, UK.
| | | | | | - Helen McShane
- The Jenner Institute, University of Oxford, Oxford, UK
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Kampmann B, Jones CE. Factors influencing innate immunity and vaccine responses in infancy. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0148. [PMID: 25964459 DOI: 10.1098/rstb.2014.0148] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Despite significant progress in reducing the burden of mortality in children under the age of five, reducing mortality in newborns remains a major challenge. Infection plays a significant role in infant deaths and interventions such as early vaccination or antenatal immunization could make a significant contribution to prevention of such deaths. In the last few years, we have gained new insights into immune ontogeny and are now beginning to understand the impact of vaccines, nutrition and environmental factors on 'training' of the immune response in early life. This review article sets out to explain why vaccine responses can be heterogeneous between populations and individuals by providing examples chosen to illustrate the impact of host, pathogen and environmental factors on shaping the immune 'interactome' in young children.
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Affiliation(s)
- Beate Kampmann
- Vaccines and Immunity Theme, MRC Unit, The Gambia, Atlantic Road, Fajara, The Gambia Academic Department of Paediatrics, Imperial College London, Norfolk Place, London, UK
| | - Christine E Jones
- Paediatric Infectious Diseases Research Group, Institute for Infection and Immunity, St George's, University of London, Cranmer Terrace, London, UK
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The impact of HIV exposure and maternal Mycobacterium tuberculosis infection on infant immune responses to bacille Calmette-Guérin vaccination. AIDS 2015; 29:155-65. [PMID: 25535752 PMCID: PMC4284011 DOI: 10.1097/qad.0000000000000536] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Objective: The objective of this study is to assess the effect of maternal HIV and Mycobacterium tuberculosis (Mtb) infection on cellular responses to bacille Calmette-Guérin (BCG) immunization. Design: A mother–infant cohort study. Methods: Samples were collected from mother–infant pairs at delivery. Infants were BCG-vaccinated at 6 weeks of age and a repeat blood sample was collected from infants at 16 weeks of age. BCG-specific T-cell proliferation and intracellular cytokine expression were measured by flow cytometry. Secreted cytokines and chemokines in cell culture supernatants were analysed using a Multiplex assay. Results: One hundred and nine (47 HIV-exposed and 62 HIV-unexposed) mother–infants pairs were recruited after delivery and followed longitudinally. At birth, proportions of mycobacteria-specific proliferating T cells were not associated with either in-utero HIV exposure or maternal Mtb sensitization. However, in-utero HIV exposure affected infant-specific T-cell subsets [tumour necrosis factor-alpha (TNF-α) single positive proliferating CD4+ T cells and interferon-gamma (IFN-γ), TNF-α dual-positive CD4+ T cells]. Levels of TNF-α protein in cell culture supernatants were also significantly higher in HIV-exposed infants born to Mtb-sensitized mothers. In the presence of maternal Mtb sensitization, frequencies of maternal and newborn BCG-specific proliferating CD4+ T cells were positively correlated. Following BCG vaccination, there was no demonstrable effect of HIV exposure or maternal Mtb infection on infant BCG-specific T-cell proliferative responses or concentrations of secreted cytokines and chemokines. Conclusion: Effects of maternal HIV and Mtb infection on infant immune profiles at birth are transient only, and HIV-exposed, noninfected infants have the same potential to respond to and be protected by BCG vaccination as HIV-unexposed infants.
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Neonatal bacillus Calmette-Guerin vaccination and environmental mycobacteria in sensitizing antimycobacterial activity of macrophages. Am J Med Sci 2014; 348:57-64. [PMID: 24374737 DOI: 10.1097/maj.0000000000000206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
An immunoepidemiological study was performed to evaluate the effect of neonatal bacillus Calmette-Guérin (BCG) vaccination and tuberculin response on macrophage killing profile against Mycobacterium tuberculosis. In this epidemiological field work, the study subjects were drawn from in and around Chennai city, South India. The descriptive epidemiological pattern of neonatal BCG vaccination and its impact on tuberculin skin test were studied. The study subjects for the immunologic laboratory experiments were recruited based on the skin test (Mantoux) outcome and were grouped in to 4 natural study groups that include vaccinated reactors, vaccinated nonreactors, nonvaccinated reactors and nonvaccinated nonreactors. In immunologic laboratory work part, the elucidation of macrophage killing profile was studied for all the 4 groups, and appropriate intercomparisons were made. The parameters used for the macrophage killing profile were (1) glutathione assay, (2) measurement of phagocytosis, (3) intracellular growth kinetics of M. tuberculosis H37Rv, (4) tumor necrosis factor-α assay and (5) interferon-γ assay. The results found that in the BCG-vaccinated tuberculin reactors the macrophage responses were significantly higher than the BCG-vaccinated tuberculin nonreactors. There was no significant difference in the responses among the BCG-vaccinated tuberculin reactors when compared with the nonvaccinated tuberculin reactors. The immune responses of nonvaccinated tuberculin reactors were significantly higher than the vaccinated tuberculin nonreactors. These findings show that the immune response among the adolescents/young adults is elicited by exposure to mycobacteria and not by the neonatal BCG vaccination.
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Harris SA, Meyer J, Satti I, Marsay L, Poulton ID, Tanner R, Minassian AM, Fletcher HA, McShane H. Evaluation of a human BCG challenge model to assess antimycobacterial immunity induced by BCG and a candidate tuberculosis vaccine, MVA85A, alone and in combination. J Infect Dis 2013; 209:1259-68. [PMID: 24273174 PMCID: PMC3969545 DOI: 10.1093/infdis/jit647] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Background. A new vaccine is urgently needed to combat tuberculosis. However, without a correlate of protection, selection of the vaccines to take forward into large-scale efficacy trials is difficult. Use of bacille Calmette-Guérin (BCG) as a surrogate for human Mycobacterium tuberculosis challenge is a novel model that could aid selection. Methods. Healthy adults were assigned to groups A and B (BCG-naive) or groups C and D (BCG-vaccinated). Groups B and D received candidate tuberculosis vaccine MVA85A. Participants were challenged with intradermal BCG 4 weeks after those who received MVA85A. Skin biopsies of the challenge site were taken 2 weeks post challenge and BCG load quantified by culture and quantitative polymerase chain reaction (qPCR). Results. Volunteers with a history of BCG showed some degree of protective immunity to challenge, having lower BCG loads compared with volunteers without prior BCG, regardless of MVA85A status. There was a significant inverse correlation between antimycobacterial immunity at peak response after MVA85A and BCG load detected by qPCR. Conclusion. Our results support previous findings that this BCG challenge model is able to detect differences in antimycobacterial immunity induced by vaccination and could aid in the selection of candidate tuberculosis vaccines for field efficacy testing. Clinical Trials Registration NCT01194180.
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32
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Meyer J, McShane H. The next 10 years for tuberculosis vaccines: do we have the right plans in place? Expert Rev Vaccines 2013; 12:443-51. [PMID: 23560924 PMCID: PMC5425624 DOI: 10.1586/erv.13.19] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The control of TB is a global health priority. Over the last decade, considerable progress has been made in the field of TB vaccines with numerous vaccine candidates entering the clinic and two candidates now in Phase IIb efficacy trials. Nevertheless, the lack of predictive animal models and biomarkers of TB vaccine efficacy prevents rational vaccine down-selection and necessitates prolonged and expensive clinical efficacy trials in target populations. Advances in molecular technology and progress in the development of human as well as animal mycobacterial challenge models make the identification of one or more immune correlates of protection a genuine prospect over the next decade. Moreover, the increasing pace, extent and coordination of global research efforts in TB promises to broaden understanding and inform the next generation of vaccine candidates against TB as well as related globally important pathogens.
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Affiliation(s)
- Joel Meyer
- The Jenner Institute, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
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Eisen S, Pealing L, Aldridge RW, Siedner MJ, Necochea A, Leybell I, Valencia T, Herrera B, Wiles S, Friedland JS, Gilman RH, Evans CA. Effects of ascent to high altitude on human antimycobacterial immunity. PLoS One 2013; 8:e74220. [PMID: 24058530 PMCID: PMC3772817 DOI: 10.1371/journal.pone.0074220] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 07/29/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Tuberculosis infection, disease and mortality are all less common at high than low altitude and ascent to high altitude was historically recommended for treatment. The immunological and mycobacterial mechanisms underlying the association between altitude and tuberculosis are unclear. We studied the effects of altitude on mycobacteria and antimycobacterial immunity. METHODS Antimycobacterial immunity was assayed in 15 healthy adults residing at low altitude before and after they ascended to 3400 meters; and in 47 long-term high-altitude residents. Antimycobacterial immunity was assessed as the extent to which participants' whole blood supported or restricted growth of genetically modified luminescent Bacille Calmette-Guérin (BCG) mycobacteria during 96 hours incubation. We developed a simplified whole blood assay that could be used by a technician in a low-technology setting. We used this to compare mycobacterial growth in participants' whole blood versus positive-control culture broth and versus negative-control plasma. RESULTS Measurements of mycobacterial luminescence predicted the number of mycobacterial colonies cultured six weeks later. At low altitude, mycobacteria grew in blood at similar rates to positive-control culture broth whereas ascent to high altitude was associated with restriction (p ≤ 0.002) of mycobacterial growth to be 4-times less than in culture broth. At low altitude, mycobacteria grew in blood 25-times more than negative-control plasma whereas ascent to high altitude was associated with restriction (p ≤ 0.01) of mycobacterial growth to be only 6-times more than in plasma. There was no evidence of differences in antimycobacterial immunity at high altitude between people who had recently ascended to high altitude versus long-term high-altitude residents. CONCLUSIONS An assay of luminescent mycobacterial growth in whole blood was adapted and found to be feasible in low-resource settings. This demonstrated that ascent to or residence at high altitude was associated with decreased mycobacterial growth in whole blood relative to controls, consistent with altitude-related augmentation of antimycobacterial cellular immunity.
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Affiliation(s)
- Sarah Eisen
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Research Department of Infection and Population Health and the School of Medicine, University College London, London, United Kingdom
| | - Louise Pealing
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Research Department of Infection and Population Health and the School of Medicine, University College London, London, United Kingdom
| | - Robert W. Aldridge
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Research Department of Infection and Population Health and the School of Medicine, University College London, London, United Kingdom
| | - Mark J. Siedner
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Innovacion Por la Salud Y el Desarollo (IPSYD), Asociación Benefica Prisma, Lima, Peru
| | - Alejandro Necochea
- Yale School of Medicine, New Haven, Connecticut, United States of America
| | - Inna Leybell
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Innovacion Por la Salud Y el Desarollo (IPSYD), Asociación Benefica Prisma, Lima, Peru
| | - Teresa Valencia
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Innovacion Por la Salud Y el Desarollo (IPSYD), Asociación Benefica Prisma, Lima, Peru
| | - Beatriz Herrera
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Innovacion Por la Salud Y el Desarollo (IPSYD), Asociación Benefica Prisma, Lima, Peru
| | - Siouxsie Wiles
- Infectious Diseases & Immunity, Imperial College London and Wellcome Trust Imperial College Centre for Global Health Research, London, United Kingdom
| | - Jon S. Friedland
- Infectious Diseases & Immunity, Imperial College London and Wellcome Trust Imperial College Centre for Global Health Research, London, United Kingdom
| | - Robert H. Gilman
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Carlton A. Evans
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development 218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru
- Infectious Diseases & Immunity, Imperial College London and Wellcome Trust Imperial College Centre for Global Health Research, London, United Kingdom
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Inhibition of mycobacterial growth in vitro following primary but not secondary vaccination with Mycobacterium bovis BCG. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 20:1683-9. [PMID: 23986316 DOI: 10.1128/cvi.00427-13] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Despite the widespread use of the Mycobacterium bovis BCG vaccine, there are more than 9 million new cases of tuberculosis (TB) every year, and there is an urgent need for better TB vaccines. TB vaccine candidates are selected for evaluation based in part on the detection of an antigen-specific gamma interferon (IFN-γ) response. The measurement of mycobacterial growth in blood specimens obtained from subjects immunized with investigational TB vaccines may be a better in vitro correlate of in vivo vaccine efficacy. We performed a clinical study with 30 United Kingdom adults who were followed for 6 months to evaluate the abilities of both a whole-blood- and a novel peripheral blood mononuclear cell (PBMC)-based mycobacterial growth inhibition assay to measure a response to primary vaccination and revaccination with BCG. Using cryopreserved PBMCs, we observed a significant improvement in mycobacterial growth inhibition following primary vaccination but no improvement in growth inhibition following revaccination with BCG (P < 0.05). Mycobacterial growth inhibition following primary BCG vaccination was not correlated with purified protein derivative (PPD) antigen-specific IFN-γ enzyme-linked immunospot (ELISPOT) responses. We demonstrate that a mycobacterial growth inhibition assay can detect improved capacity to control growth following primary immunization, but not revaccination, with BCG. This is the first study to demonstrate that an in vitro growth inhibition assay can identify a difference in vaccine responses by comparing both primary and secondary BCG vaccinations, suggesting that in vitro growth inhibition assays may serve as better surrogates of clinical efficacy than the assays currently used for the assessment of candidate TB vaccines.
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Mycobacterial growth inhibition in murine splenocytes as a surrogate for protection against Mycobacterium tuberculosis (M. tb). Tuberculosis (Edinb) 2013; 93:551-7. [PMID: 23726784 DOI: 10.1016/j.tube.2013.04.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 04/19/2013] [Accepted: 04/23/2013] [Indexed: 11/20/2022]
Abstract
Development of an improved vaccine against tuberculosis (TB) is hindered by the lack of a surrogate of protection. Efficacy of new TB vaccines in humans can only be evaluated by expensive and time consuming efficacy trials within TB endemic areas. It is critical that vaccines with the greatest potential to protect are selected for these trials. Mycobacterial growth inhibition assays (MGIAs) have been developed with the hope that these in-vitro functional assays will correlate with protection, which could aid in the selection of the best vaccine candidates. The present study describes the use of the BACTEC system to perform MGIAs in mice. We demonstrate reproducible mycobacterial growth inhibition in splenocytes from BCG immunised mice compared with unimmunised mice (P < 0.023), which corresponded with in-vivo efficacy against Mycobacterium tuberculosis (M. tb) challenge. Microarray data showed extensive differential gene expression in splenocyte responses to ex-vivo BCG stimulation between unimmunised and BCG-immunised mice. TH1 responses, including IFN-γ, nitric oxide synthase (NOS2) and Interleukin -17 (IL-17) expression were enhanced in BCG immunised mice, indicating a possible mechanism for mycobacterial growth inhibition. Further investigation into whether the BACTEC MGIA can be used as a surrogate of protection in humans and preclinical animal models is now warranted.
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Burl S, Holder BS, Lo BKM, Kampmann B. Optimisation of a functional mycobacterial growth-inhibition assay to improve its suitability for infant TB vaccine studies. J Immunol Methods 2013; 394:121-4. [PMID: 23707325 PMCID: PMC3725412 DOI: 10.1016/j.jim.2013.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 05/14/2013] [Accepted: 05/16/2013] [Indexed: 11/22/2022]
Abstract
The development of vaccines against tuberculosis continues to be hindered by the lack of correlates of protection. Immunity to Mycobacterium tuberculosis (M.tb) infection relies predominantly on cell mediated response, which is routinely measured using a read-out of host cytokine profiles. However, to date none of the cytokine profiles have been found to predict protection. A number of functional in vitro approaches that measure growth of mycobacteria pre- and post-vaccination as a potential functional surrogate marker for vaccine take have been developed. The use of a reporter-gene tagged BCG-lux assay measuring the viability of mycobacteria in whole blood samples has previously been described by our group to assess vaccine immunogenicity. Since only very small blood samples are usually available in paediatric studies, we now report a modification of the BCG-lux assay to reduce the volume required and make it more field-friendly. Our results show that a 2-fold reduction in blood volume made no significant difference to bacterial growth ratios, used as the main read-out. These results confirm the suitability of the BCG-lux assay for functional studies of vaccine immunogenicity and immunopathogenesis in young children and could play a role in late-phase TB vaccine trials of novel candidates. A 2-fold reduction in blood volume can now be used in a functional BCG-lux assay. This growth-restriction assay is a useful tool for vaccine assessment. Reduction in blood volumes will aid its use in trials of TB vaccines in infants.
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Affiliation(s)
- S Burl
- Department of Paediatrics, St Mary's Campus, Imperial College London, Norfolk Place, London W2 1PG, UK.
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Wallis RS, Kim P, Cole S, Hanna D, Andrade BB, Maeurer M, Schito M, Zumla A. Tuberculosis biomarkers discovery: developments, needs, and challenges. THE LANCET. INFECTIOUS DISEASES 2013; 13:362-72. [DOI: 10.1016/s1473-3099(13)70034-3] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Romano M, Huygen K. An update on vaccines for tuberculosis – there is more to it than just waning of BCG efficacy with time. Expert Opin Biol Ther 2012; 12:1601-10. [DOI: 10.1517/14712598.2012.721768] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Franzblau SG, DeGroote MA, Cho SH, Andries K, Nuermberger E, Orme IM, Mdluli K, Angulo-Barturen I, Dick T, Dartois V, Lenaerts AJ. Comprehensive analysis of methods used for the evaluation of compounds against Mycobacterium tuberculosis. Tuberculosis (Edinb) 2012; 92:453-88. [PMID: 22940006 DOI: 10.1016/j.tube.2012.07.003] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/02/2012] [Accepted: 07/09/2012] [Indexed: 02/01/2023]
Abstract
In drug development, there are typically a series of preclinical studies that must be completed with new compounds or regimens before use in humans. A sequence of in vitro assays followed by in vivo testing in validated animal models to assess the activity against Mycobacterium tuberculosis, pharmacology and toxicity is generally used for advancing compounds against tuberculosis in a preclinical stage. A plethora of different assay systems and conditions are used to study the effect of drug candidates on the growth of M. tuberculosis, making it difficult to compare data from one laboratory to another. The Bill and Melinda Gates Foundation recognized the scientific gap to delineate the spectrum of variables in experimental protocols, identify which of these are biologically significant, and converge towards a rationally derived standard set of optimized assays for evaluating compounds. The goals of this document are to recommend protocols and hence accelerate the process of TB drug discovery and testing. Data gathered from preclinical in vitro and in vivo assays during personal visits to laboratories and an electronic survey of methodologies sent to investigators is reported. Comments, opinions, experiences as well as final recommendations from those currently engaged in such preclinical studies for TB drug testing are being presented. Certain in vitro assays and mouse efficacy models were re-evaluated in the laboratory as head-to-head experiments and a summary is provided on the results obtained. It is our hope that this information will be a valuable resource for investigators in the field to move forward in an efficient way and that key variables of assays are included to ensure accuracy of results which can then be used for designing human clinical trials. This document then concludes with remaining questions and critical gaps that are in need of further validation and experimentation.
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Affiliation(s)
- Scott G Franzblau
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, 833 S Wood Street, Chicago, IL 60621-7231, USA
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Ritz N, Strach M, Yau C, Dutta B, Tebruegge M, Connell TG, Hanekom WA, Britton WJ, Robins-Browne R, Curtis N. A comparative analysis of polyfunctional T cells and secreted cytokines induced by Bacille Calmette-Guérin immunisation in children and adults. PLoS One 2012; 7:e37535. [PMID: 22829867 PMCID: PMC3400612 DOI: 10.1371/journal.pone.0037535] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 04/20/2012] [Indexed: 11/30/2022] Open
Abstract
BCG vaccine is one of the most commonly-administered vaccines worldwide. Studies suggest the protective efficacy of BCG against TB is better for children than for adults. One potential explanation is that BCG induces a better protective immune response in children. Twenty six children and adults were immunised with BCG. The proportion of Th1-cytokine-producing mycobacterial-specific T cells, and the concentrations of secreted cytokines, were measured before and 10 weeks after BCG immunisation. A significant increase in the proportion of mycobacterial-specific cytokine-producing T cells was observed in both age groups. After BCG immunisation, children and adults had comparable proportions of mycobacterial-specific polyfunctional CD4 T cells when measured relative to the total number of CD4 T cells. However, relative to the subset of Th-1-cytokine-producing CD4 T cells, the proportion of polyfunctional cells was greater in children. Concentrations of secreted cytokines were comparable in children and adults. These findings suggest that the mycobacterial-specific cell-mediated immune response induced by BCG immunisation in children and adults is similar. The implication of a shift to a more polyfunctional immune response within the Th1-cytokine-producing CD4 T cells in children is uncertain as this aspect of the immune response has not been assessed as a potential correlate of protection against TB.
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Affiliation(s)
- Nicole Ritz
- Department of Paediatrics, The University of Melbourne, Parkville, Australia.
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Newton S, Martineau A, Kampmann B. A functional whole blood assay to measure viability of mycobacteria, using reporter-gene tagged BCG or M.Tb (BCGlux/M.Tb lux). J Vis Exp 2011:3332. [PMID: 21946922 DOI: 10.3791/3332] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Functional assays have long played a key role in measuring of immunogenicity of a given vaccine. This is conventionally expressed as serum bactericidal titers. Studies of serum bactericidal titers in response to childhood vaccines have enabled us to develop and validate cut-off levels for protective immune responses and such cut-offs are in routine use. No such assays have been taken forward into the routine assessment of vaccines that induce primarily cell-mediated immunity in the form of effector T cell responses, such as TB vaccines. In the animal model, the performance of a given vaccine candidate is routinely evaluated in standardized bactericidal assays, and all current novel TB-vaccine candidates have been subjected to this step in their evaluation prior to phase 1 human trials. The assessment of immunogenicity and therefore likelihood of protective efficacy of novel anti-TB vaccines should ideally undergo a similar step-wise evaluation in the human models now, including measurements in bactericidal assays. Bactericidal assays in the context of tuberculosis vaccine research are already well established in the animal models, where they are applied to screen potentially promising vaccine candidates. Reduction of bacterial load in various organs functions as the main read-out of immunogenicity. However, no such assays have been incorporated into clinical trials for novel anti-TB vaccines to date. Although there is still uncertainty about the exact mechanisms that lead to killing of mycobacteria inside human macrophages, the interaction of macrophages and T cells with mycobacteria is clearly required. The assay described in this paper represents a novel generation of bactericidal assays that enables studies of such key cellular components with all other cellular and humoral factors present in whole blood without making assumptions about their relative individual contribution. The assay described by our group uses small volumes of whole blood and has already been employed in studies of adults and children in TB-endemic settings. We have shown immunogenicity of the BCG vaccine, increased growth of mycobacteria in HIV-positive patients, as well as the effect of anti-retroviral therapy and Vitamin D on mycobacterial survival in vitro. Here we summarise the methodology, and present our reproducibility data using this relatively simple, low-cost and field-friendly model. Note: Definitions/Abbreviations BCG lux = M. bovis BCG, Montreal strain, transformed with shuttle plasmid pSMT1 carrying the luxAB genes from Vibrio harveyi, under the control of the mycobacterial GroEL (hsp60) promoter. CFU = Colony Forming Unit (a measure of mycobacterial viability).
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Affiliation(s)
- Sandra Newton
- Department of Paediatrics, Imperial College London, UK
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Checkley AM, McShane H. Tuberculosis vaccines: progress and challenges. Trends Pharmacol Sci 2011; 32:601-6. [PMID: 21803435 DOI: 10.1016/j.tips.2011.06.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 06/15/2011] [Accepted: 06/15/2011] [Indexed: 11/18/2022]
Abstract
An effective tuberculosis (TB) vaccine could have a significant impact on the current TB pandemic. The past decade has seen sustained global investment into reaching this goal; currently there are several promising vaccines in clinical trials. Current strategies include the development of an improved bacille Calmette-Guerin (BCG) vaccine to be given at birth and a booster vaccine to be administered after BCG. Here, we describe the current vaccination strategy and review the main issues in novel TB vaccine development. Potential vaccine candidates are evaluated in pre-clinical animal models, and the most promising go into clinical testing; a vaccine candidate is evaluated in at least one model before progressing to early clinical trials. The main challenge in early trials is the lack of a defined correlate of vaccine-induced immune protection. Following this, large efficacy trials are undertaken, which face the daunting challenges of cost, logistics and trial site capacity.
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Affiliation(s)
- Anna M Checkley
- Jenner Institute, Nuffield Department of Medicine, Oxford University, ORCRB, Roosevelt Drive, Oxford OX3 7DQ, UK
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Wallis RS, Pai M, Menzies D, Doherty TM, Walzl G, Perkins MD, Zumla A. Biomarkers and diagnostics for tuberculosis: progress, needs, and translation into practice. Lancet 2010; 375:1920-37. [PMID: 20488517 DOI: 10.1016/s0140-6736(10)60359-5] [Citation(s) in RCA: 302] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Human infection with Mycobacterium tuberculosis can progress to active disease, be contained as latent infection, or be eradicated by the host response. Tuberculosis diagnostics classify a patient into one of these categories. These are not fixed distinct states, but rather are continua along which patients can move, and are affected by HIV infection, immunosuppressive therapies, antituberculosis treatments, and other poorly understood factors. Tuberculosis biomarkers-host or pathogen-specific-provide prognostic information, either for individual patients or study cohorts, about these outcomes. Tuberculosis case detection remains difficult, partly because of inaccurate diagnostic methods. Investments have yielded some progress in development of new diagnostics, although the existing pipeline is limited for tests for sputum-smear-negative cases, childhood tuberculosis, and accurate prediction of reactivation of latent tuberculosis. Despite new, sensitive, automated molecular platforms for detection of tuberculosis and drug resistance, a simple, inexpensive point-of-care test is still not available. The effect of any new tests will depend on the method and extent of their introduction, the strength of the laboratories, and the degree to which access to appropriate therapy follows access to diagnosis. Translation of scientific progress in biomarkers and diagnostics into clinical and public health programmes is possible-with political commitment, increased funding, and engagement of all stakeholders.
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Andreu N, Zelmer A, Fletcher T, Elkington PT, Ward TH, Ripoll J, Parish T, Bancroft GJ, Schaible U, Robertson BD, Wiles S. Optimisation of bioluminescent reporters for use with mycobacteria. PLoS One 2010; 5:e10777. [PMID: 20520722 PMCID: PMC2875389 DOI: 10.1371/journal.pone.0010777] [Citation(s) in RCA: 229] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 04/27/2010] [Indexed: 01/01/2023] Open
Abstract
Background Mycobacterium tuberculosis, the causative agent of tuberculosis, still represents a major public health threat in many countries. Bioluminescence, the production of light by luciferase-catalyzed reactions, is a versatile reporter technology with multiple applications both in vitro and in vivo. In vivo bioluminescence imaging (BLI) represents one of its most outstanding uses by allowing the non-invasive localization of luciferase-expressing cells within a live animal. Despite the extensive use of luminescent reporters in mycobacteria, the resultant luminescent strains have not been fully applied to BLI. Methodology/Principal Findings One of the main obstacles to the use of bioluminescence for in vivo imaging is the achievement of reporter protein expression levels high enough to obtain a signal that can be detected externally. Therefore, as a first step in the application of this technology to the study of mycobacterial infection in vivo, we have optimised the use of firefly, Gaussia and bacterial luciferases in mycobacteria using a combination of vectors, promoters, and codon-optimised genes. We report for the first time the functional expression of the whole bacterial lux operon in Mycobacterium tuberculosis and M. smegmatis thus allowing the development of auto-luminescent mycobacteria. We demonstrate that the Gaussia luciferase is secreted from bacterial cells and that this secretion does not require a signal sequence. Finally we prove that the signal produced by recombinant mycobacteria expressing either the firefly or bacterial luciferases can be non-invasively detected in the lungs of infected mice by bioluminescence imaging. Conclusions/Significance While much work remains to be done, the finding that both firefly and bacterial luciferases can be detected non-invasively in live mice is an important first step to using these reporters to study the pathogenesis of M. tuberculosis and other mycobacterial species in vivo. Furthermore, the development of auto-luminescent mycobacteria has enormous ramifications for high throughput mycobacterial drug screening assays which are currently carried out either in a destructive manner using LuxAB or the firefly luciferase.
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Affiliation(s)
- Nuria Andreu
- Department of Medicine, Imperial College London, London, United Kingdom
| | - Andrea Zelmer
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Taryn Fletcher
- Department of Medicine, Imperial College London, London, United Kingdom
| | - Paul T. Elkington
- Department of Medicine, Imperial College London, London, United Kingdom
| | - Theresa H. Ward
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jorge Ripoll
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
| | - Tanya Parish
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
- Infectious Diseases Research Institute, Seattle, Washington, United States of America
| | - Gregory J. Bancroft
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Ulrich Schaible
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Molecular Infection Research, Research Center Borstel, Borstel, Germany
| | | | - Siouxsie Wiles
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
- * E-mail:
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Biomarkers for tuberculosis disease activity, cure, and relapse. THE LANCET. INFECTIOUS DISEASES 2009; 9:162-72. [DOI: 10.1016/s1473-3099(09)70042-8] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Wallis RS. Reactivation of latent tuberculosis by TNF blockade: the role of interferon gamma. J Investig Dermatol Symp Proc 2007; 12:16-21. [PMID: 17502864 DOI: 10.1038/sj.jidsymp.5650031] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tumor necrosis factor (TNF) plays a pathogenic role in psoriasis and rheumatoid arthritis but is essential for host defenses against mycobacteria and other granulomatous pathogens. The risk of reactivation of latent Mycobacterium tuberculosis infection is significantly greater with the TNF monoclonal antibody infliximab than with the soluble TNF-receptor etanercept. We have examined the biologic basis of this difference using whole blood culture. Infliximab and adalimumab reduced the proportion of T buciclate-responsive cells by 70 and 50%, respectively, and suppressed antigen-induced IFN-gamma production by 70 and 64%. In contrast, etanercept produced no significant effect. The difference between infliximab and etanercept remained whether one compared equal or peak therapeutic drug concentrations, suggesting a relationship to mechanism of action rather than pharmacokinetics. Adalimumab and etanercept caused divergent, concentration dependent effects on control of intracellular growth of M. tuberculosis. None of the drugs induced significant levels of apoptosis or necrosis in monocytes or T cells, excluding T-cell death as a mechanism for suppression of antigen-induced responses. IL-10 production was equally suppressed by all three drugs, excluding excess IL-10 as a regulatory mechanism. The tuberculosis risk posed by infliximab may reflect its combined effects on TNF and IFNgamma.
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Castro-Rodriguez JA, Mallol J, Andrade R, Muñoz M, Azzini I. Comparison of tuberculin skin test response after three modalities of neonatal BCG vaccination. Trans R Soc Trop Med Hyg 2007; 101:493-6. [PMID: 16997338 DOI: 10.1016/j.trstmh.2006.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Revised: 08/18/2006] [Accepted: 08/21/2006] [Indexed: 11/29/2022] Open
Abstract
The aim of this study was to determine the tuberculin skin test (TST) response to three different BCG modalities [0.1 ml Tokyo (n=104), 0.05 ml Pasteur-Mérieux (n=137) and 0.1 ml Pasteur-Mérieux (n=100)] in a cohort of healthy newborns 5 months after vaccination at birth in Santiago, Chile. Among the 341 infants, 91.2% had a response to TST, and the mean+/-SD TST reaction size was significantly larger in infants receiving the Tokyo strain than in those receiving the 0.05 ml or 0.1 ml Pasteur-Mérieux strains (4.4+/-2.0, 3.5+/-1.3 and 3.1+/-1.4 mm, respectively; P<0.0001). The mean+/-SD of the BCG scar size was significantly lower in infants vaccinated with the Tokyo strain than in those vaccinated with the 0.1 ml Pasteur-Mérieux strain (3.9+/-1.2 vs. 4.3+/-1.1 mm; P=0.03) and no significant difference was found between infants receiving the Tokyo strain and the 0.05 ml Pasteur-Mérieux strain. However, the differences in TST size induced by diverse BCG vaccination modalities may not reflect the quality of the immunologically induced response in terms of TB protection.
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Affiliation(s)
- Jose A Castro-Rodriguez
- Department of Pediatric Respiratory Medicine, Faculty of Medical Sciences, Hospital CRS El Pino, University of Santiago de Chile, Santiago, Chile.
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Nicol MP, Kampmann B, Lawrence P, Wood K, Pienaar S, Pienaar D, Eley B, Levin M, Beatty D, Anderson STB. Enhanced anti-mycobacterial immunity in children with erythema nodosum and a positive tuberculin skin test. J Invest Dermatol 2007; 127:2152-7. [PMID: 17460727 DOI: 10.1038/sj.jid.5700845] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Erythema nodosum (EN) may follow a variety of infections, but in regions with a high prevalence of tuberculosis, is frequently associated with a positive tuberculin skin test (TST) and tuberculosis infection. We aimed to investigate the immunological differences between patients with EN as a manifestation of primary tuberculosis, and those with progressive pulmonary tuberculosis (PTB) or asymptomatic infection. We studied the inflammatory response to both mycobacterial and non-mycobacterial antigens in 11 children with EN associated with a positive TST, 22 children with culture-confirmed tuberculosis, and 53 healthy skin test-positive children. In addition, we evaluated functional anti-mycobacterial immunity using an ex vivo assay of mycobacterial growth restriction in five children with EN and 15 with PTB. Patients with EN were distinguished by enhanced mycobacterial growth restriction on the functional assay, which was associated with a markedly increased production of IFNgamma in response to stimulation with purified protein derivative of Mycobacterium tuberculosis. Children presenting with EN and a positive TST show evidence of responses associated with enhanced anti-mycobacterial immunity.
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Affiliation(s)
- Mark P Nicol
- School of Child and Adolescent Health, Red Cross Children's Hospital, University of Cape Town, Cape Town, Western Cape, South Africa.
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Al-Attiyah R, El-Shazly A, Mustafa AS. Assessment of in vitro immunity to Mycobacterium tuberculosis in a human peripheral blood infection model using a luciferase reporter construct of M. tuberculosis H37Rv. Clin Exp Immunol 2006; 145:520-7. [PMID: 16907922 PMCID: PMC1809703 DOI: 10.1111/j.1365-2249.2006.03133.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Protective immune responses to tuberculosis in man are primarily cell-mediated and require the interaction of specific T cells, cytokines and activated macrophages. In the present study, Mycobacterium tuberculosis H37Rv labelled with luciferase reporter enzyme was used to analyse the anti-mycobacterial immunity in man using an in vitro whole blood infection model. Peripheral blood samples obtained from M. bovis bacille Calmette-Guérin (BCG)-vaccinated tuberculin-positive healthy volunteers (n = 23) were cultured with M. tuberculosis H37Rv reporter strain. The growth of bacteria in the whole blood cultures was monitored after 48 and 96 h of infection. The results showed that the growth of M. tuberculosis was significantly inhibited after 96 h (P < 0.029) of culture. Among the cytokines studied, interleukin (IL)-10 and IL-12 were not detected at all, whereas low levels of interferon (IFN)-gamma after 96 h (0.4 IU/ml) and tumour necrosis factor (TNF)-alpha after 48 (135 pg/ml) and 96 h (47 pg/ml) of culture were detected in the supernatants of whole blood infected with M. tuberculosis. The magnitude of bacterial growth correlated directly with the concentration of TNF-alpha detected after 48 h (r = 0.722) and 96 h (r = 0.747) of culture (P <or= 0.0001 and P <or= 0.0001, respectively). However, the addition of monoclonal antibodies specific to TNF-alpha and IFN-gamma to the blood cultures did not alter mycobacterial growth indicating the role of other mechanisms/factors in restricting the growth of M. tuberculosis in whole blood cultures.
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Affiliation(s)
- R Al-Attiyah
- Department of Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait.
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