1
|
Chong DLW, Mikolasch TA, Sahota J, Rebeyrol C, Garthwaite HS, Booth HL, Heightman M, Denneny EK, José RJ, Khawaja AA, Duckworth A, Labelle M, Scotton CJ, Porter JC. Investigating the role of platelets and platelet-derived transforming growth factor-β in idiopathic pulmonary fibrosis. Am J Physiol Lung Cell Mol Physiol 2023; 325:L487-L499. [PMID: 37643008 PMCID: PMC10639018 DOI: 10.1152/ajplung.00227.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 07/17/2023] [Accepted: 08/18/2023] [Indexed: 08/31/2023] Open
Abstract
Transforming growth factor-β1 (TGFβ1) is the key profibrotic cytokine in idiopathic pulmonary fibrosis (IPF), but the primary source of this cytokine in this disease is unknown. Platelets have abundant stores of TGFβ1, although the role of these cells in IPF is ill-defined. In this study, we investigated whether platelets, and specifically platelet-derived TGFβ1, mediate IPF disease progression. Patients with IPF and non-IPF patients were recruited to determine platelet reactivity, and separate cohorts of patients with IPF were followed for mortality. To study whether platelet-derived TGFβ1 modulates pulmonary fibrosis (PF), mice with a targeted deletion of TGFβ1 in megakaryocytes and platelets (TGFβ1fl/fl.PF4-Cre) were used in the well-characterized bleomycin-induced pulmonary fibrosis (PF) animal model. In a discovery cohort, we found significantly higher mortality in patients with IPF who had elevated platelet counts within the normal range. However, our validation cohort did not confirm this observation, despite significantly increased platelets, neutrophils, active TGFβ1, and CCL5, a chemokine produced by inflammatory cells, in the blood, lung, and bronchoalveolar lavage (BAL) of patients with IPF. In vivo, we showed that despite platelets being readily detected within the lungs of bleomycin-treated mice, neither the degree of pulmonary inflammation nor fibrosis was significantly different between TGFβ1fl/fl.PF4-Cre and control mice. Our results demonstrate for the first time that platelet-derived TGFβ1 does not significantly mediate inflammation or fibrosis in a PF animal model. Furthermore, our human studies revealed blood platelet counts do not consistently predict mortality in IPF but other platelet-derived mediators, such as C-C chemokine ligand 5 (CCL5), may promote neutrophil recruitment and human IPF.NEW & NOTEWORTHY Platelets are a rich source of profibrotic TGFβ; however, the role of platelets in idiopathic pulmonary fibrosis (IPF) is unclear. We identified that patients with IPF have significantly more platelets, neutrophils, and active TGFβ in their airways than control patients. Using an animal model of IPF, we demonstrated that platelet-derived TGFβ does not significantly drive lung fibrosis or inflammation. Our findings offer a better understanding of platelets in both human and animal studies of IPF.
Collapse
Affiliation(s)
- Deborah L W Chong
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
- Institute for Infection and Immunity, St George's University of London, London, United Kingdom
| | - Theresia A Mikolasch
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Jagdeep Sahota
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Carine Rebeyrol
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Helen S Garthwaite
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Helen L Booth
- Interstitial Lung Disease Service, University College London Hospital, London, United Kingdom
| | - Melissa Heightman
- Interstitial Lung Disease Service, University College London Hospital, London, United Kingdom
| | - Emma K Denneny
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Ricardo J José
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Akif A Khawaja
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| | - Anna Duckworth
- Department of Clinical and Biomedical Science, University of Exeter, Exeter, United Kingdom
| | - Myriam Labelle
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States
| | - Chris J Scotton
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
- Department of Clinical and Biomedical Science, University of Exeter, Exeter, United Kingdom
| | - Joanna C Porter
- UCL Respiratory, Division of Medicine, University College London, London, United Kingdom
| |
Collapse
|
2
|
Whittington AM, Turner FS, Baark F, Templeman S, Kirwan DE, Roufosse C, Krishnan N, Robertson BD, Chong DLW, Porter JC, Gilman RH, Friedland JS. An acidic microenvironment in Tuberculosis increases extracellular matrix degradation by regulating macrophage inflammatory responses. PLoS Pathog 2023; 19:e1011495. [PMID: 37418488 PMCID: PMC10355421 DOI: 10.1371/journal.ppat.1011495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 07/19/2023] [Accepted: 06/20/2023] [Indexed: 07/09/2023] Open
Abstract
Mycobacterium tuberculosis (M.tb) infection causes marked tissue inflammation leading to lung destruction and morbidity. The inflammatory extracellular microenvironment is acidic, however the effect of this acidosis on the immune response to M.tb is unknown. Using RNA-seq we show that acidosis produces system level transcriptional change in M.tb infected human macrophages regulating almost 4000 genes. Acidosis specifically upregulated extracellular matrix (ECM) degradation pathways with increased expression of Matrix metalloproteinases (MMPs) which mediate lung destruction in Tuberculosis. Macrophage MMP-1 and -3 secretion was increased by acidosis in a cellular model. Acidosis markedly suppresses several cytokines central to control of M.tb infection including TNF-α and IFN-γ. Murine studies demonstrated expression of known acidosis signaling G-protein coupled receptors OGR-1 and TDAG-8 in Tuberculosis which are shown to mediate the immune effects of decreased pH. Receptors were then demonstrated to be expressed in patients with TB lymphadenitis. Collectively, our findings show that an acidic microenvironment modulates immune function to reduce protective inflammatory responses and increase extracellular matrix degradation in Tuberculosis. Acidosis receptors are therefore potential targets for host directed therapy in patients.
Collapse
Affiliation(s)
| | - Frances S. Turner
- Edinburgh Genomics, University of Edinburgh, Edinburgh, United Kingdom
| | - Friedrich Baark
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Sam Templeman
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Daniela E. Kirwan
- Institute of Infection and Immunity, St. George’s, University of London, London, United Kingdom
| | - Candice Roufosse
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Nitya Krishnan
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Brian D. Robertson
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Deborah L. W. Chong
- Institute of Infection and Immunity, St. George’s, University of London, London, United Kingdom
| | - Joanna C. Porter
- Centre for Inflammation & Tissue Repair, Respiratory Medicine, University College London, London, United Kingdom
| | - Robert H. Gilman
- Department of International Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jon S. Friedland
- Institute of Infection and Immunity, St. George’s, University of London, London, United Kingdom
| |
Collapse
|
3
|
Chong DLW, Rebeyrol C, José RJ, Williams AE, Brown JS, Scotton CJ, Porter JC. ICAM-1 and ICAM-2 Are Differentially Expressed and Up-Regulated on Inflamed Pulmonary Epithelium, but Neither ICAM-2 nor LFA-1: ICAM-1 Are Required for Neutrophil Migration Into the Airways In Vivo. Front Immunol 2021; 12:691957. [PMID: 34484188 PMCID: PMC8415445 DOI: 10.3389/fimmu.2021.691957] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/29/2021] [Indexed: 01/21/2023] Open
Abstract
Neutrophil migration into the airways is an important process to fight infection and is mediated by cell adhesion molecules. The intercellular adhesion molecules, ICAM-1 (CD54) and ICAM-2 (CD102) are known ligands for the neutrophil integrins, lymphocyte function associated antigen (LFA)-1 (αLβ2; CD11a/CD18), and macrophage-1 antigen (Mac-1;αMβ2;CD11b/CD18) and are implicated in leukocyte migration into the lung. However, it is ill-defined how neutrophils exit the lung and the role for ICAMs in trans-epithelial migration (TEpM) across the bronchial or alveolar epithelium. We found that human and murine alveolar epithelium expressed ICAM-1, whilst the bronchial epithelium expressed ICAM-2, and both were up-regulated during inflammatory stimulation in vitro and in inflammatory lung diseases such as cystic fibrosis. Although β2 integrins interacting with ICAM-1 and -2 mediated neutrophil migration across human bronchial epithelium in vitro, neither ICAM-2 nor LFA-1 binding of ICAM-1 mediated murine neutrophil migration into the lung or broncho-alveolar space during LPS-induced inflammation in vivo. Furthermore, TEpM of neutrophils themselves resulted in increased epithelial junctional permeability and reduced barrier function in vitro. This suggests that although β2 integrins interacting with ICAMs may regulate low levels of neutrophil traffic in healthy lung or early in inflammation when the epithelial barrier is intact; these interactions may be redundant later in inflammation when epithelial junctions are disrupted and no longer limit TEpM.
Collapse
Affiliation(s)
- Deborah L. W. Chong
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
| | - Carine Rebeyrol
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
| | - Ricardo J. José
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
| | - Andrew E. Williams
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
| | - Jeremy S. Brown
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
| | - Chris J. Scotton
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
- Institute of Biomedical and Clinical Sciences, College of Medicine & Health, Exeter, United Kingdom
| | - Joanna C. Porter
- Centre for Inflammation and Tissue Repair, Division of Medicine, University College London, London, United Kingdom
| |
Collapse
|
4
|
Abstract
In 2019 10 million people developed symptomatic tuberculosis (TB) disease and 1.2 million died. In active TB the inflammatory response causes tissue destruction, which leads to both acute morbidity and mortality. Tissue destruction in TB is driven by host innate immunity and mediated via enzymes, chiefly matrix metalloproteinases (MMPs) which are secreted by leukocytes and stromal cells and degrade the extracellular matrix. Here we review the growing evidence implicating platelets in TB immunopathology. TB patients typically have high platelet counts, which correlate with disease severity, and a hypercoagulable profile. Platelets are present in human TB granulomas and platelet-associated gene transcripts are increased in TB patients versus healthy controls. Platelets most likely drive TB immunopathology through their effect on other immune cells, particularly monocytes, to lead to upregulation of activation markers, increased MMP secretion, and enhanced phagocytosis. Finally, we consider current evidence supporting use of targeted anti-platelet agents in the treatment of TB due to growing interest in developing host-directed therapies to limit tissue damage and improve treatment outcomes. In summary, platelets are implicated in TB disease and contribute to MMP-mediated tissue damage via their cellular interactions with other leukocytes, and are potential targets for novel host-directed therapies.
Collapse
Affiliation(s)
- Daniela E Kirwan
- Institute for Infection & Immunity, St. George's, University of London, London, United Kingdom
| | - Deborah L W Chong
- Institute for Infection & Immunity, St. George's, University of London, London, United Kingdom
| | - Jon S Friedland
- Institute for Infection & Immunity, St. George's, University of London, London, United Kingdom
| |
Collapse
|
5
|
Khawaja AA, Chong DLW, Sahota J, Mikolasch TA, Pericleous C, Ripoll VM, Booth HL, Khan S, Rodriguez-Justo M, Giles IP, Porter JC. Identification of a Novel HIF-1α-α Mβ 2 Integrin-NET Axis in Fibrotic Interstitial Lung Disease. Front Immunol 2020; 11:2190. [PMID: 33178179 PMCID: PMC7594517 DOI: 10.3389/fimmu.2020.02190] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/11/2020] [Indexed: 12/18/2022] Open
Abstract
Neutrophilic inflammation correlates with mortality in fibrotic interstitial lung disease (ILD) particularly in the most severe form, idiopathic pulmonary fibrosis (IPF), although the underlying mechanisms remain unclear. Neutrophil function is modulated by numerous factors, including integrin activation, inflammatory cytokines and hypoxia. Hypoxia has an important role in inflammation and may also contribute to pulmonary disease. We aimed to determine how neutrophil activation occurs in ILD and the relative importance of hypoxia. Using lung biopsies and bronchoalveolar lavage (BAL) fluid from ILD patients we investigated the extent of hypoxia and neutrophil activation in ILD lungs. Then we used ex vivo neutrophils isolated from healthy volunteers and BAL from patients with ILD and non-ILD controls to further investigate aberrant neutrophil activation in hypoxia and ILD. We demonstrate for the first time using intracellular staining, HIF-1α stabilization in neutrophils and endothelial cells in ILD lung biopsies. Hypoxia enhanced both spontaneous (+1.31-fold, p < 0.05) and phorbol 12-myristate 13-acetate (PMA)-induced (+1.65-fold, p < 0.001) neutrophil extracellular trap (NET) release, neutrophil adhesion (+8.8-fold, <0.05), and trans-endothelial migration (+1.9-fold, p < 0.05). Hypoxia also increased neutrophil expression of the αM (+3.1-fold, p < 0.001) and αX (+1.6-fold, p < 0.01) integrin subunits. Interestingly, NET formation was induced by αMβ2 integrin activation and prevented by cation chelation. Finally, we observed NET-like structures in IPF lung sections and in the BAL from ILD patients, and quantification showed increased cell-free DNA content (+5.5-fold, p < 0.01) and MPO-citrullinated histone H3 complexes (+21.9-fold, p < 0.01) in BAL from ILD patients compared to non-ILD controls. In conclusion, HIF-1α upregulation may augment neutrophil recruitment and activation within the lung interstitium through activation of β2 integrins. Our results identify a novel HIF-1α- αMβ2 integrin axis in NET formation for future exploration in therapeutic approaches to fibrotic ILD.
Collapse
Affiliation(s)
- Akif A. Khawaja
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
- Centre for Rheumatology, University College London, London, United Kingdom
| | - Deborah L. W. Chong
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
| | - Jagdeep Sahota
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
| | - Theresia A. Mikolasch
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
- Interstitial Lung Disease Service, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Charis Pericleous
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Vera M. Ripoll
- Centre for Rheumatology, University College London, London, United Kingdom
| | - Helen L. Booth
- Interstitial Lung Disease Service, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Saif Khan
- Institute of Nuclear Medicine, University College London, London, United Kingdom
| | - Manuel Rodriguez-Justo
- Department of Histopathology, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Ian P. Giles
- Centre for Rheumatology, University College London, London, United Kingdom
| | - Joanna C. Porter
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
- Interstitial Lung Disease Service, University College London Hospital NHS Foundation Trust, London, United Kingdom
| |
Collapse
|
6
|
Chong DLW, Trinder S, Labelle M, Rodriguez-Justo M, Hughes S, Holmes AM, Scotton CJ, Porter JC. Platelet-derived transforming growth factor-β1 promotes keratinocyte proliferation in cutaneous wound healing. J Tissue Eng Regen Med 2020; 14:645-649. [PMID: 32068954 PMCID: PMC7216944 DOI: 10.1002/term.3022] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 11/25/2019] [Accepted: 01/27/2020] [Indexed: 01/08/2023]
Abstract
Platelets are a recognised potent source of transforming growth factor‐β1 (TGFβ1), a cytokine known to promote wound healing and regeneration by stimulating dermal fibroblast proliferation and extracellular matrix deposition. Platelet lysate has been advocated as a novel personalised therapeutic to treat persistent wounds, although the precise platelet‐derived growth factors responsible for these beneficial effects have not been fully elucidated. The aim of this study was to investigate the specific role of platelet‐derived TGFβ1 in cutaneous wound healing. Using a transgenic mouse with a targeted deletion of TGFβ1 in megakaryocytes and platelets (TGFβ1fl/fl.PF4‐Cre), we show for the first time that platelet‐derived TGFβ1 contributes to epidermal and dermal thickening and cellular turnover after excisional skin wounding. In vitro studies demonstrate that human dermal fibroblasts stimulated with platelet lysate containing high levels of platelet‐derived TGFβ1 did not exhibit enhanced collagen deposition or proliferation, suggesting that platelet‐derived TGFβ1 is not a key promoter of these wound healing processes. Interestingly, human keratinocytes displayed enhanced TGFβ1‐driven proliferation in response to platelet lysate, reminiscent of our in vivo findings. In summary, our novel findings define and emphasise an important role of platelet‐derived TGFβ1 in epidermal remodelling and regeneration processes during cutaneous wound healing.
Collapse
Affiliation(s)
- Deborah L W Chong
- Centre for Inflammation and Tissue Repair, UCL, Bloomsbury Campus, London, UK
| | - Sarah Trinder
- Department of Inflammation, UCL, Royal Free Campus, London, UK
| | - Myriam Labelle
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | | | - Sian Hughes
- Department of Histopathology, UCL, Bloomsbury Campus, London, UK
| | - Alan M Holmes
- Department of Inflammation, UCL, Royal Free Campus, London, UK.,Drug Discovery Group, Translational Research Office, School of Pharmacy, UCL, London, UK
| | - Chris J Scotton
- Centre for Inflammation and Tissue Repair, UCL, Bloomsbury Campus, London, UK.,Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Joanna C Porter
- Centre for Inflammation and Tissue Repair, UCL, Bloomsbury Campus, London, UK
| |
Collapse
|
7
|
Reynolds CJ, Chong DLW, Li Y, Black SL, Cutler A, Webster Z, Manji J, Altmann DM, Boyton RJ. Bioluminescent Reporting of In Vivo IFN-γ Immune Responses during Infection and Autoimmunity. J Immunol 2019; 202:2502-2510. [PMID: 30814307 PMCID: PMC6452029 DOI: 10.4049/jimmunol.1801453] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/30/2019] [Indexed: 12/17/2022]
Abstract
IFN-γ is a key cytokine of innate and adaptive immunity. It is important to understand temporal changes in IFN-γ production and how these changes relate to the role of IFN-γ in diverse models of infectious and autoimmune disease, making the ability to monitor and track IFN-γ production in vivo of a substantial benefit. IFN-γ ELISPOTs have been a central methodology to measure T cell immunity for many years. In this study, we add the capacity to analyze IFN-γ responses with high sensitivity and specificity, longitudinally, in vitro and in vivo. This allows the refinement of experimental protocols because immunity can be tracked in real-time through a longitudinal approach. We have generated a novel murine IFN-γ reporter transgenic model that allows IFN-γ production to be visualized and quantified in vitro and in vivo as bioluminescence using an imaging system. At baseline, in the absence of an inflammatory stimulus, IFN-γ signal from lymphoid tissue is detectable in vivo. Reporter transgenics are used in this study to track the IFN-γ response to Pseudomonas aeruginosa infection in the lung over time in vivo. The longitudinal development of the adaptive T cell immunity following immunization with Ag is identified from day 7 in vivo. Finally, we show that we are able to use this reporter transgenic to follow the onset of autoimmune T cell activation after regulatory T cell depletion in an established model of systemic autoimmunity. This IFN-γ reporter transgenic, termed “Gammaglow,” offers a valuable new modality for tracking IFN-γ immunity, noninvasively and longitudinally over time.
Collapse
Affiliation(s)
- Catherine J Reynolds
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| | - Deborah L W Chong
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| | - Yihan Li
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| | - S Lucas Black
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| | - Amy Cutler
- Transgenics and Embryonic Stem Cell Facility, Medical Research Council London Institute of Medical Sciences, London W12 ONN, United Kingdom
| | - Zoe Webster
- Transgenics and Embryonic Stem Cell Facility, Medical Research Council London Institute of Medical Sciences, London W12 ONN, United Kingdom
| | - Jiten Manji
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| | - Daniel M Altmann
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| | - Rosemary J Boyton
- Lung Immunology Group, Infectious Diseases and Immunity, Department of Medicine, Imperial College London, London W12 ONN, United Kingdom; and
| |
Collapse
|
8
|
Brilha S, Chong DLW, Khawaja AA, Ong CWM, Guppy NJ, Porter JC, Friedland JS. Integrin α2β1 Expression Regulates Matrix Metalloproteinase-1-Dependent Bronchial Epithelial Repair in Pulmonary Tuberculosis. Front Immunol 2018; 9:1348. [PMID: 29988449 PMCID: PMC6024194 DOI: 10.3389/fimmu.2018.01348] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/31/2018] [Indexed: 11/22/2022] Open
Abstract
Pulmonary tuberculosis (TB) is caused by inhalation of Mycobacterium tuberculosis, which damages the bronchial epithelial barrier to establish local infection. Matrix metalloproteinase-1 plays a crucial role in the immunopathology of TB, causing breakdown of type I collagen and cavitation, but this collagenase is also potentially involved in bronchial epithelial repair. We hypothesized that the extracellular matrix (ECM) modulates M. tuberculosis-driven matrix metalloproteinase-1 expression by human bronchial epithelial cells (HBECs), regulating respiratory epithelial cell migration and repair. Medium from monocytes stimulated with M. tuberculosis induced collagenase activity in bronchial epithelial cells, which was reduced by ~87% when cells were cultured on a type I collagen matrix. Matrix metalloproteinase-1 had a focal localization, which is consistent with cell migration, and overall secretion decreased by 32% on type I collagen. There were no associated changes in the specific tissue inhibitors of metalloproteinases. Decreased matrix metalloproteinase-1 secretion was due to ligand-binding to the α2β1 integrin and was dependent on the actin cytoskeleton. In lung biopsies, samples from patients with pulmonary TB, integrin α2β1 is highly expressed on the bronchial epithelium. Areas of lung with disrupted collagen matrix showed an increase in matrix metalloproteinases-1 expression compared with areas where collagen was comparable to control lung. Type I collagen matrix increased respiratory epithelial cell migration in a wound-healing assay, and this too was matrix metalloproteinase-dependent, since it was blocked by the matrix metalloproteinase inhibitor GM6001. In summary, we report a novel mechanism by which α2β1-mediated signals from the ECM modulate matrix metalloproteinase-1 secretion by HBECs, regulating their migration and epithelial repair in TB.
Collapse
Affiliation(s)
- Sara Brilha
- Infectious Diseases and Immunity, Imperial College London, London, United Kingdom.,Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
| | - Deborah L W Chong
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
| | - Akif A Khawaja
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
| | - Catherine W M Ong
- Infectious Diseases and Immunity, Imperial College London, London, United Kingdom.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Naomi J Guppy
- UCL Advanced Diagnostics, University College London, London, United Kingdom
| | - Joanna C Porter
- Centre for Inflammation and Tissue Repair, University College London, London, United Kingdom
| | - Jon S Friedland
- Infectious Diseases and Immunity, Imperial College London, London, United Kingdom
| |
Collapse
|
9
|
|
10
|
Turner CE, Sommerlad M, McGregor K, Davies FJ, Pichon B, Chong DLW, Farzaneh L, Holden MTG, Spratt BG, Efstratiou A, Sriskandan S. Superantigenic activity of emm3 Streptococcus pyogenes is abrogated by a conserved, naturally occurring smeZ mutation. PLoS One 2012; 7:e46376. [PMID: 23049698 PMCID: PMC3462185 DOI: 10.1371/journal.pone.0046376] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 08/29/2012] [Indexed: 11/18/2022] Open
Abstract
Streptococcus pyogenes M/emm3 strains have been epidemiologically linked with enhanced infection severity and risk of streptococcal toxic shock syndrome (STSS), a syndrome triggered by superantigenic stimulation of T cells. Comparison of S. pyogenes strains causing STSS demonstrated that emm3 strains were surprisingly less mitogenic than other emm-types (emm1, emm12, emm18, emm28, emm87, emm89) both in vitro and in vivo, indicating poor superantigenic activity. We identified a 13 bp deletion in the superantigen smeZ gene of all emm3 strains tested. The deletion led to a premature stop codon in smeZ, and was not present in other major emm-types tested. Expression of a functional non-M3-smeZ gene successfully enhanced mitogenic activity in emm3 S. pyogenes and also restored mitogenic activity to emm1 and emm89 S. pyogenes strains where the smeZ gene had been disrupted. In contrast, the M3-smeZ gene with the 13 bp deletion could not enhance or restore mitogenicity in any of these S. pyogenes strains, confirming that M3-smeZ is non-functional regardless of strain background. The mutation in M3-smeZ reduced the potential for M3 S. pyogenes to induce cytokines in human tonsil, but not during invasive infection of superantigen-sensitive mice. Notwithstanding epidemiological associations with STSS and disease severity, emm3 strains have inherently poor superantigenicity that is explained by a conserved mutation in smeZ.
Collapse
Affiliation(s)
- Claire E. Turner
- Department of Infectious Diseases & Immunity, Imperial College London, London, United Kingdom
| | - Mary Sommerlad
- Department of Infectious Diseases & Immunity, Imperial College London, London, United Kingdom
| | - Karen McGregor
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Frances J. Davies
- Department of Infectious Diseases & Immunity, Imperial College London, London, United Kingdom
| | - Bruno Pichon
- Respiratory and Systemic Infection Laboratory, The Health Protection Agency Centre for Infections, London, United Kingdom
| | - Deborah L. W. Chong
- Department of Infectious Diseases & Immunity, Imperial College London, London, United Kingdom
| | - Leili Farzaneh
- Department of Infectious Diseases & Immunity, Imperial College London, London, United Kingdom
| | - Matthew T. G. Holden
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Brian G. Spratt
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Androulla Efstratiou
- Respiratory and Systemic Infection Laboratory, The Health Protection Agency Centre for Infections, London, United Kingdom
| | - Shiranee Sriskandan
- Department of Infectious Diseases & Immunity, Imperial College London, London, United Kingdom
- * E-mail:
| |
Collapse
|
11
|
Chong DLW, Ingram RJ, Lowther DE, Muir R, Sriskandan S, Altmann DM. The nature of innate and adaptive interleukin-17A responses in sham or bacterial inoculation. Immunology 2012; 136:325-33. [PMID: 22384827 DOI: 10.1111/j.1365-2567.2012.03584.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Streptococcus pyogenes is the causative agent of numerous diseases ranging from benign infections (pharyngitis and impetigo) to severe infections associated with high mortality (necrotizing fasciitis and bacterial sepsis). As with other bacterial infections, there is considerable interest in characterizing the contribution of interleukin-17A (IL-17A) responses to protective immunity. We here show significant il17a up-regulation by quantitative real-time PCR in secondary lymphoid organs, correlating with increased protein levels in the serum within a short time of S. pyogenes infection. However, our data offer an important caveat to studies of IL-17A responsiveness following antigen inoculation, because enhanced levels of IL-17A were also detected in the serum of sham-infected mice, indicating that inoculation trauma alone can stimulate the production of this cytokine. This highlights the potency and speed of innate IL-17A immune responses after inoculation and the importance of proper and appropriate controls in comparative analysis of immune responses observed during microbial infection.
Collapse
Affiliation(s)
- Deborah L W Chong
- Section of Infectious Diseases & Immunity, Imperial College, Hammersmith Hospital, London Centre for Infection & Immunity, Queen's University, Belfast, UK
| | | | | | | | | | | |
Collapse
|
12
|
Abstract
Sepsis is characterised by a hyper-inflammatory response due to microbial infection. We here review our current understanding of host mechanisms employed to mediate this hyper-inflammatory response, drawing together current knowledge pertaining to pathogen recognition and host pro-inflammatory response. Recognition of microbial derived ligands by pattern recognition receptors (PRRs) is a key step in initiating pro-inflammatory signalling pathways. Examples of PRRs linked to the aetiology of sepsis include Toll-like, C-type lectin, RIG-1-like and also Nod-like receptors, which are involved in the formation of the inflammasome, crucial for the maturation of some pro-inflammatory cytokines. Bacterial superantigens have evolved to exploit host MHC class II and T cell receptors (normally considered part of the adaptive immune response) as innate PRRs to propagate a so-called 'cytokine storm', while synergy between different microbial ligands and host-derived alarmins can augment the inflammatory response still further through as yet poorly understood interactions. The host pro-inflammatory response results in the characteristic features of inflammation: rubor, calor, dolor, and tumor. We will review herein the key mediators of inflammation in sepsis, identifying their overlapping and intersecting roles in vascular changes in tone, endothelial permeability, coagulation and contact activation, leukocyte mobilisation and activation.
Collapse
|