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Yang Y, Jia M, Ou Y, Adcock IM, Yao X. Mechanisms and biomarkers of airway epithelial cell damage in asthma: A review. CLINICAL RESPIRATORY JOURNAL 2021; 15:1027-1045. [PMID: 34097803 DOI: 10.1111/crj.13407] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 05/17/2021] [Accepted: 06/03/2021] [Indexed: 12/15/2022]
Abstract
Bronchial asthma is a heterogeneous disease with complex pathological mechanisms representing different phenotypes, including severe asthma. The airway epithelium is a major site of complex pathological changes in severe asthma due, in part, to activation of inflammatory and immune mechanisms in response to noxious agents. Current imaging procedures are unable to accurately measure epithelial and airway remodeling. Damage of airway epithelial cells occurs is linked to specific phenotypes and endotypes which provides an opportunity for the identification of biomarkers reflecting epithelial, and airway, remodeling. Identification of patients with more severe epithelial disruption using biomarkers may also provide personalised therapeutic opportunities and/or markers of successful therapeutic intervention. Here, we review the evidence for ongoing epithelial cell dysregulation in the pathogenesis of asthma, the sentinel role of the airway epithelium and how understanding these molecular mechanisms provides the basis for the identification of candidate biomarkers for asthma prediction, prevention, diagnosis, treatment and monitoring.
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Affiliation(s)
- Yuemei Yang
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Man Jia
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yingwei Ou
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Department of Emergency Medical, Zhejiang Province People's Hospital, Zhejiang, China
| | - Ian M Adcock
- Airway Disease Section, National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Xin Yao
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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2
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Persson C. In vivo observations provide insight into roles of eosinophils and epithelial cells in asthma. Eur Respir J 2019; 54:13993003.00470-2019. [PMID: 31248957 DOI: 10.1183/13993003.00470-2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/18/2019] [Indexed: 01/10/2023]
Abstract
Observations in vivo in patients, supported by guinea-pig in vivo data, take centre stage in this perspective. Its objective is to highlight dichotomies between asthma features observed in vivo and accepted views involving cell/molecular biology research paradigms. For example, increased bronchial epithelial permeability is now considered a major paradigm and trait of asthma, yet, absorption of inhaled tracers has not been increased in vivo in asthma. Such maintained barrier function in exudative asthma reflects in vivo asymmetry of the epithelial lining as barrier between outside and inside world of molecules and cells. In desquamatory asthma, maintained epithelial tightness may be explained by in vivo demonstrations of exceedingly patchy epithelial loss, prompt creation of plasma-derived provisional barriers, and high-speed epithelial regeneration. Acknowledged protein/peptide secretion by epithelial cells in vitro is contrasted here with a dominant, unidirectional movement in vivo of plasma-derived proteins/peptides (including antimicrobial peptides) to the surface of an intact epithelial lining. Furthermore, longstanding claims that epithelium-produced adenosine is a mediator of asthma are eroded by observations in vivo in asthmatics. Notions concerning activation/fate of mucosal tissue eosinophils illustrate additional distinctions between accepted views and in vivo patient observations. Finally, in vitro-based paradigms preaching defect epithelial regeneration and increased permeability in pathogenesis of asthma are contrasted with experimental in vivo observations of exaggerated epithelial regeneration, which is multipathogenic in its own right. In conclusion, unexpected and challenging in vivo observations in recent decades underpin novel insights into mucosal mechanisms in asthma.
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Affiliation(s)
- Carl Persson
- Laboratory Medicine University Hospital, Lund, Sweden
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3
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Nurwati I, Purwanto B, Mudigdo A, Saputra K, Prasetyo DH, Muthmainah M. Improvement in inflammation and airway remodelling after acupuncture at BL13 and ST36 in a mouse model of chronic asthma. Acupunct Med 2019; 37:228-236. [PMID: 31155877 DOI: 10.1177/0964528418818705] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Asthma is a chronic inflammatory disease that affects millions of people worldwide. Chronic asthma is commonly resistant to steroid therapy. Acupuncture has an anti-inflammatory effect and has been widely used as an add-on therapy for asthma. OBJECTIVE To evaluate the effects of acupuncture on the inflammatory response and airway remodelling in the bronchioles of an asthma mouse model. METHODS A chronic asthma model was produced in female BALB/c mice by ovalbumin (OVA) sensitisation. 32 mice were randomised into four groups: control; asthma (OVA); OVA+BL13; and OVA+BL13+ST36. OVA was administered by intraperitoneal injection on days 0 and 14 followed by aerosol exposure of 1% OVA three times a week for 6 weeks. Manual acupuncture (MA) was performed three times a week for 6 weeks at BL13 alone, or BL13 in combination with ST36, in the two MA-treated groups. At the end of the experiment, blood samples were collected to determine eosinophil and neutrophil counts and lung tissue was prepared for histological examination. RESULTS A pronounced reduction in the neutrophil count was achieved after MA at BL13+ST36 (P=0.005) while the eosinophil count was lowered after MA both at BL13 (P=0.007) and BL13+ST36 (P=0.006). Reduction in the bronchiolar epithelial and smooth muscle thickness and the number of goblet cells was observed after MA at BL13 (P=0.001, P=0.001 and P=0.002, respectively) and BL13+ST36 (P=0.001, P=0.002 and P=0.001, respectively). CONCLUSION Acupuncture can reduce the inflammatory response and prevent airway remodelling in a chronic asthma mouse model.
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Affiliation(s)
- Ida Nurwati
- 1 Faculty of Medicine, Universitas Sebelas Maret, Indonesia.,2 Doctoral Program in Medical Science, Postgraduate Program, Universitas Sebelas Maret, Surakarta, Indonesia
| | - Bambang Purwanto
- 1 Faculty of Medicine, Universitas Sebelas Maret, Indonesia.,2 Doctoral Program in Medical Science, Postgraduate Program, Universitas Sebelas Maret, Surakarta, Indonesia.,3 Department of Internal Medicine, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Indonesia
| | - Ambar Mudigdo
- 1 Faculty of Medicine, Universitas Sebelas Maret, Indonesia.,2 Doctoral Program in Medical Science, Postgraduate Program, Universitas Sebelas Maret, Surakarta, Indonesia.,4 Department of Anatomic Pathology, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Indonesia
| | - Koosnadi Saputra
- 5 Acupuncture Research Laboratory in Health Services, Ministry of Health of Republic Indonesia, South Jakarta, Indonesia.,6 Academy Acupuncture of Surabaya, Surabaya, Indonesia
| | - Diding Heri Prasetyo
- 1 Faculty of Medicine, Universitas Sebelas Maret, Indonesia.,3 Department of Internal Medicine, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Indonesia
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4
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Persson C. Airways exudation of plasma macromolecules: Innate defense, epithelial regeneration, and asthma. J Allergy Clin Immunol 2018; 143:1271-1286. [PMID: 30170125 PMCID: PMC7112321 DOI: 10.1016/j.jaci.2018.07.037] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 06/30/2018] [Accepted: 07/13/2018] [Indexed: 01/09/2023]
Abstract
This review discusses in vivo airway aspects of plasma exudation in relation to current views on epithelial permeability and epithelial regeneration in health and disease. Microvascular-epithelial exudation of bulk plasma proteins characteristically occurs in asthmatic patients, being especially pronounced in those with severe and exacerbating asthma. Healthy human and guinea pig airways challenged by noninjurious histamine-leukotriene–type autacoids also respond through prompt mucosal exudation of nonsieved plasma macromolecules. Contrary to current beliefs, epithelial permeability in the opposite direction (ie, absorption of inhaled molecules) has not been increased in patients with asthma and allergic rhinitis or in acutely exuding healthy airways. A slightly increased subepithelial hydrostatic pressure produces such unidirectional outward perviousness to macromolecules. Lack of increased absorption permeability in asthmatic patients can further be reconciled with occurrence of epithelial shedding, leaving small patches of denuded basement membrane. Counteracting escalating barrier breaks, plasma exudation promptly covers the denuded patches. Here it creates and sustains a biologically active barrier involving a neutrophil-rich, fibrin-fibronectin net. Furthermore, in the plasma-derived milieu, all epithelial cell types bordering the denuded patch dedifferentiate and migrate from all sides to cover the denuded basement membrane. However, this speedy epithelial regeneration can come at a cost. Guinea pig in vivo studies demonstrate that patches of epithelial denudation regeneration are exudation hot spots evoking asthma-like features, including recruitment/activation of granulocytes, proliferation of fibrocytes/smooth muscle cells, and basement membrane thickening. In conclusion, nonsieved plasma macromolecules can operate on the intact airway mucosa as potent components of first-line innate immunity responses. Exuded plasma also takes center stage in epithelial regeneration. When exaggerated, epithelial regeneration can contribute to the inception and development of asthma.
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Affiliation(s)
- Carl Persson
- Department of Laboratory Medicine, University Hospital of Lund, Lund, Sweden.
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Burg D, Schofield JPR, Brandsma J, Staykova D, Folisi C, Bansal A, Nicholas B, Xian Y, Rowe A, Corfield J, Wilson S, Ward J, Lutter R, Fleming L, Shaw DE, Bakke PS, Caruso M, Dahlen SE, Fowler SJ, Hashimoto S, Horváth I, Howarth P, Krug N, Montuschi P, Sanak M, Sandström T, Singer F, Sun K, Pandis I, Auffray C, Sousa AR, Adcock IM, Chung KF, Sterk PJ, Djukanović R, Skipp PJ, The U-Biopred Study Group. Large-Scale Label-Free Quantitative Mapping of the Sputum Proteome. J Proteome Res 2018; 17:2072-2091. [PMID: 29737851 DOI: 10.1021/acs.jproteome.8b00018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Analysis of induced sputum supernatant is a minimally invasive approach to study the epithelial lining fluid and, thereby, provide insight into normal lung biology and the pathobiology of lung diseases. We present here a novel proteomics approach to sputum analysis developed within the U-BIOPRED (unbiased biomarkers predictive of respiratory disease outcomes) international project. We present practical and analytical techniques to optimize the detection of robust biomarkers in proteomic studies. The normal sputum proteome was derived using data-independent HDMSE applied to 40 healthy nonsmoking participants, which provides an essential baseline from which to compare modulation of protein expression in respiratory diseases. The "core" sputum proteome (proteins detected in ≥40% of participants) was composed of 284 proteins, and the extended proteome (proteins detected in ≥3 participants) contained 1666 proteins. Quality control procedures were developed to optimize the accuracy and consistency of measurement of sputum proteins and analyze the distribution of sputum proteins in the healthy population. The analysis showed that quantitation of proteins by HDMSE is influenced by several factors, with some proteins being measured in all participants' samples and with low measurement variance between samples from the same patient. The measurement of some proteins is highly variable between repeat analyses, susceptible to sample processing effects, or difficult to accurately quantify by mass spectrometry. Other proteins show high interindividual variance. We also highlight that the sputum proteome of healthy individuals is related to sputum neutrophil levels, but not gender or allergic sensitization. We illustrate the importance of design and interpretation of disease biomarker studies considering such protein population and technical measurement variance.
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Affiliation(s)
- Dominic Burg
- Centre for Proteomic Research, Biological Sciences , University of Southampton , Southampton SO17 1BJ , U.K.,NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - James P R Schofield
- Centre for Proteomic Research, Biological Sciences , University of Southampton , Southampton SO17 1BJ , U.K.,NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Joost Brandsma
- NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Doroteya Staykova
- Centre for Proteomic Research, Biological Sciences , University of Southampton , Southampton SO17 1BJ , U.K
| | - Caterina Folisi
- Centre for Proteomic Research, Biological Sciences , University of Southampton , Southampton SO17 1BJ , U.K
| | | | - Ben Nicholas
- NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Yang Xian
- Data Science Institute , Imperial College London , London SW7 2AZ , U.K
| | - Anthony Rowe
- Janssen Research & Development , Buckinghamshire HP12 4DP , U.K
| | | | - Susan Wilson
- NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Jonathan Ward
- NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Rene Lutter
- AMC, Department of Experimental Immunology , University of Amsterdam , 1012 WX Amsterdam , The Netherlands.,AMC, Department of Respiratory Medicine , University of Amsterdam , 1012 WX Amsterdam , The Netherlands
| | - Louise Fleming
- Airways Disease , National Heart and Lung Institute, Imperial College, London & Royal Brompton NIHR Biomedical Research Unit , London SW7 2AZ , United Kingdom
| | - Dominick E Shaw
- Respiratory Research Unit , University of Nottingham , Nottingham NG7 2RD , U.K
| | - Per S Bakke
- Institute of Medicine , University of Bergen , 5007 Bergen , Norway
| | - Massimo Caruso
- Department of Clinical and Experimental Medicine Hospital University , University of Catania , 95124 Catania , Italy
| | - Sven-Erik Dahlen
- The Centre for Allergy Research , The Institute of Environmental Medicine, Karolinska Institutet , SE-171 77 Stockholm , Sweden
| | - Stephen J Fowler
- Respiratory and Allergy Research Group , University of Manchester , Manchester M13 9PL , U.K
| | - Simone Hashimoto
- Department of Respiratory Medicine, Academic Medical Centre , University of Amsterdam , 1012 WX Amsterdam , The Netherlands
| | - Ildikó Horváth
- Department of Pulmonology , Semmelweis University , Budapest 1085 , Hungary
| | - Peter Howarth
- NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Norbert Krug
- Fraunhofer Institute for Toxicology and Experimental Medicine Hannover , 30625 Hannover , Germany
| | - Paolo Montuschi
- Faculty of Medicine , Catholic University of the Sacred Heart , 00168 Rome , Italy
| | - Marek Sanak
- Laboratory of Molecular Biology and Clinical Genetics, Medical College , Jagiellonian University , 31-007 Krakow , Poland
| | - Thomas Sandström
- Department of Medicine, Department of Public Health and Clinical Medicine Respiratory Medicine Unit , Umeå University , 901 87 Umeå , Sweden
| | - Florian Singer
- University Children's Hospital Zurich , 8032 Zurich , Switzerland
| | - Kai Sun
- Data Science Institute , Imperial College London , London SW7 2AZ , U.K
| | - Ioannis Pandis
- Data Science Institute , Imperial College London , London SW7 2AZ , U.K
| | - Charles Auffray
- European Institute for Systems Biology and Medicine, CNRS-ENS-UCBL-INSERM , Université de Lyon , 69007 Lyon , France
| | - Ana R Sousa
- Respiratory Therapeutic Unit, GSK , Stockley Park , Uxbridge UB11 1BT , U.K
| | - Ian M Adcock
- Cell and Molecular Biology Group, Airways Disease Section , National Heart and Lung Institute, Imperial College London , Dovehouse Street , London SW3 6LR , U.K
| | - Kian Fan Chung
- Airways Disease , National Heart and Lung Institute, Imperial College, London & Royal Brompton NIHR Biomedical Research Unit , London SW7 2AZ , United Kingdom
| | - Peter J Sterk
- AMC, Department of Experimental Immunology , University of Amsterdam , 1012 WX Amsterdam , The Netherlands
| | - Ratko Djukanović
- NIHR Southampton Biomedical Research Centre, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton SO16 6YD , U.K
| | - Paul J Skipp
- Centre for Proteomic Research, Biological Sciences , University of Southampton , Southampton SO17 1BJ , U.K
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Kasaian MT, Lee J, Brennan A, Danto SI, Black KE, Fitz L, Dixon AE. Proteomic analysis of serum and sputum analytes distinguishes controlled and poorly controlled asthmatics. Clin Exp Allergy 2018; 48:814-824. [PMID: 29665127 DOI: 10.1111/cea.13151] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 03/11/2018] [Accepted: 03/28/2018] [Indexed: 12/27/2022]
Abstract
BACKGROUND A major goal of asthma therapy is to achieve disease control, with maintenance of lung function, reduced need for rescue medication, and prevention of exacerbation. Despite current standard of care, up to 70% of patients with asthma remain poorly controlled. Analysis of serum and sputum biomarkers could offer insights into parameters associated with poor asthma control. OBJECTIVE To identify signatures as determinants of asthma disease control, we performed proteomics using Olink proximity extension analysis. METHODS Up to 3 longitudinal serum samples were collected from 23 controlled and 25 poorly controlled asthmatics. Nine of the controlled and 8 of the poorly controlled subjects also provided 2 longitudinal sputum samples. The study included an additional cohort of 9 subjects whose serum was collected within 48 hours of asthma exacerbation. Two separate pre-defined Proseek Multiplex panels (INF and CVDIII) were run to quantify 181 separate protein analytes in serum and sputum. RESULTS Panels consisting of 9 markers in serum (CCL19, CCL25, CDCP1, CCL11, FGF21, FGF23, Flt3L, IL-10Rβ, IL-6) and 16 markers in sputum (tPA, KLK6, RETN, ADA, MMP9, Chit1, GRN, PGLYRP1, MPO, HGF, PRTN3, DNER, PI3, Chi3L1, AZU1, and OPG) distinguished controlled and poorly controlled asthmatics. The sputum analytes were consistent with a pattern of neutrophil activation associated with poor asthma control. The serum analyte profile of the exacerbation cohort resembled that of the controlled group rather than that of the poorly controlled asthmatics, possibly reflecting a therapeutic response to systemic corticosteroids. CONCLUSIONS AND CLINICAL RELEVANCE Proteomic profiles in serum and sputum distinguished controlled and poorly controlled asthmatics, and were maintained over time. Findings support a link between sputum neutrophil markers and loss of asthma control.
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Affiliation(s)
- M T Kasaian
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, Massachusetts, USA
| | - J Lee
- Early Clinical Development, Pfizer, Cambridge, Massachusetts, USA
| | - A Brennan
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, Massachusetts, USA
| | - S I Danto
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, Massachusetts, USA
| | - K E Black
- Department of Medicine, University of Vermont, Burlington, Vermont, USA
| | - L Fitz
- Early Clinical Development, Pfizer, Cambridge, Massachusetts, USA
| | - A E Dixon
- Department of Medicine, University of Vermont, Burlington, Vermont, USA
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Hastie AT, Steele C, Dunaway CW, Moore WC, Rector BM, Ampleford E, Li H, Denlinger LC, Jarjour N, Meyers DA, Bleecker ER. Complex association patterns for inflammatory mediators in induced sputum from subjects with asthma. Clin Exp Allergy 2018. [PMID: 29520864 DOI: 10.1111/cea.13129] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND The release of various inflammatory mediators into the bronchial lumen is thought to reflect both the type and degree of airway inflammation, eosinophilic Th2, and Th9, or neutrophilic Th1, and Th17, in patients with asthma. AIMS We investigated whether cytokines and chemokines differed in sputum from subjects with more severe compared with milder asthma and whether unbiased factor analysis of cytokine and chemokine groupings indicates specific inflammatory pathways. METHODS Cell-free supernatants from induced sputum were obtained from subjects with a broad range of asthma severity (n = 158) and assessed using Milliplex® Cytokines/Chemokine kits I, II and III, measuring 75 individual proteins. Each cytokine, chemokine or growth factor concentration was examined for differences between asthma severity groups, for association with leucocyte counts, and by factor analysis. RESULTS Severe asthma subjects had 9 increased and 4 decreased proteins compared to mild asthma subjects and fewer differences compared to moderate asthma. Twenty-six mediators were significantly associated with an increasing single leucocyte type: 16 with neutrophils (3 interleukins [IL], 3 CC chemokines, 4 CXC chemokines, 4 growth factors, TNF-α and CX3CL1/Fractalkine); 5 with lymphocytes (IL-7, IL-16, IL-23, IFN-α2 and CCL4/MIP1β); IL-15 and CCL15/MIP1δ with macrophages; IL-5 with eosinophils; and IL-4 and TNFSF10/TRAIL with airway epithelial cells. Factor analysis grouped 43 cytokines, chemokines and growth factors which had no missing data onto the first 10 factors, containing mixes of Th1, Th2, Th9 and Th17 inflammatory and anti-inflammatory proteins. CONCLUSIONS Sputum cytokines, chemokines and growth factors were increased in severe asthma, primarily with increased neutrophils. Factor analysis identified complex inflammatory protein interactions, suggesting airway inflammation in asthma is characterized by overlapping immune pathways. Thus, focus on a single specific inflammatory mediator or pathway may limit understanding the complexity of inflammation underlying airway changes in asthma and selection of appropriate therapy.
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Affiliation(s)
- A T Hastie
- Department of Internal Medicine, Section on Pulmonary, Critical Care, Allergy and Immunology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - C Steele
- Lung Immunology of Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - C W Dunaway
- Lung Immunology of Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - W C Moore
- Department of Internal Medicine, Section on Pulmonary, Critical Care, Allergy and Immunology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - B M Rector
- Department of Internal Medicine, Section on Pulmonary, Critical Care, Allergy and Immunology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - E Ampleford
- Department of Internal Medicine, Section on Pulmonary, Critical Care, Allergy and Immunology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - H Li
- University of Arizona College of Medicine, Tucson, AZ, USA
| | - L C Denlinger
- Department of Medicine, University of Wisconsin, Madison, WI, USA
| | - N Jarjour
- Department of Medicine, University of Wisconsin, Madison, WI, USA
| | - D A Meyers
- University of Arizona College of Medicine, Tucson, AZ, USA
| | - E R Bleecker
- University of Arizona College of Medicine, Tucson, AZ, USA
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8
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Uwaezuoke SN, Ayuk AC, Eze JN. Severe bronchial asthma in children: a review of novel biomarkers used as predictors of the disease. J Asthma Allergy 2018; 11:11-18. [PMID: 29398922 PMCID: PMC5774744 DOI: 10.2147/jaa.s149577] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Severe asthma or therapy-resistant asthma in children is a heterogeneous disease that affects all age-groups. Given its heterogeneity, precision in diagnosis and treatment has become imperative, in order to achieve better outcomes. If one is thus able to identify specific patient phenotypes and endotypes using the appropriate biomarkers, it will assist in providing the patient with more personalized and appropriate treatment. However, there appears to be a huge diagnostic gap in severe asthma, as there is no single test yet that accurately determines disease phenotype. In this paper, we review the published literature on some of these biomarkers and their possible role in bridging this diagnostic gap. We also highlight the cellular and molecular mechanisms involved in severe asthma, in order to show the basis for the novel biomarkers. Some markers useful for monitoring therapy and assessing airway remodeling in the disease are also discussed. A review of the literature was conducted with PubMed to gather baseline data on the subject. The literature search extended to articles published within the last 40 years. Although biomarkers specific to different severe asthma phenotypes have been identified, progress in their utility remains slow, because of several disease mechanisms, the variation of biomarkers at different levels of inflammation, changes in relying on one test over time (eg, from sputum eosinophilia to blood eosinophilia), and the degree of invasive tests required to collect biomarkers, which limits their applicability in clinical settings. In conclusion, several biomarkers remain useful in recognizing various asthma phenotypes. However, due to disease heterogeneity, identification and utilization of ideal and defined biomarkers in severe asthma are still inconclusive. The development of novel serum/sputum-based biomarker panels with enhanced sensitivity and specificity may lead to prompt diagnosis of the disease in the future.
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Affiliation(s)
- Samuel N Uwaezuoke
- Department of Pediatrics, University of Nigeria Teaching Hospital, Ituku-Ozalla, Nigeria
| | - Adaeze C Ayuk
- Department of Pediatrics, University of Nigeria Teaching Hospital, Ituku-Ozalla, Nigeria
| | - Joy N Eze
- Department of Pediatrics, University of Nigeria Teaching Hospital, Ituku-Ozalla, Nigeria
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9
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Fricker M, Heaney LG, Upham JW. Can biomarkers help us hit targets in difficult-to-treat asthma? Respirology 2017; 22:430-442. [PMID: 28248008 DOI: 10.1111/resp.13014] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 01/19/2017] [Accepted: 01/21/2017] [Indexed: 12/16/2022]
Abstract
Biomarkers may be a key foundation for the precision medicine of the future. In this article, we review current knowledge regarding biomarkers in difficult-to-treat asthma and their ability to guide the use of both conventional asthma therapies and novel (targeted) therapies. Biomarkers (as measured by tests including prednisolone and cortisol assays and the fractional exhaled nitric oxide (NO) suppression test) show promise in the assessment and management of non-adherence to inhaled and oral corticosteroids. Multiple markers of type 2 inflammation have been developed, including eosinophils in sputum and blood, exhaled NO, serum IgE and periostin. Although these show potential in guiding the selection of novel interventions for refractory type 2 inflammation in asthma, and in determining if the desired response is being achieved, it is becoming clear that different biomarkers reflect distinct components of the complex type 2 inflammatory pathways. Less progress has been made in identifying biomarkers for use in difficult-to-treat asthma that is not associated with type 2 inflammation. The future is likely to see further biomarker discovery, direct measurements of individual cytokines rather than surrogates of their activity and the increasing use of biomarkers in combination. If the promise of biomarkers is to be fulfilled, they will need to provide useful information that aids clinical decision-making, rather than being 'just another test' for clinicians to order.
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Affiliation(s)
- Michael Fricker
- Centre of Excellence in Severe Asthma, School of Medicine and Public Health, Hunter Medical Research Institute, University of Newcastle, Newcastle, New South Wales, Australia
| | - Liam G Heaney
- Centre for Experimental Medicine, Wellcome-Wolfson Institute for Experimental Medicine, Queens University Belfast, Belfast, UK
| | - John W Upham
- Translational Research Institute, The University of Queensland, Brisbane, Queensland, Australia.,Department of Respiratory and Sleep Medicine, Princess Alexandra Hospital, Brisbane, Queensland, Australia
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10
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Ghebre MA, Desai D, Singapuri A, Woods J, Rapley L, Cohen S, Herath A, Wardlaw AJ, Pashley CH, May R, Brightling CE. Sputum Inflammatory Mediators Are Increased in Aspergillus fumigatus Culture-Positive Asthmatics. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2017; 9:177-181. [PMID: 28102063 PMCID: PMC5266110 DOI: 10.4168/aair.2017.9.2.177] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 07/05/2016] [Accepted: 07/15/2016] [Indexed: 12/15/2022]
Abstract
Aspergillus fumigatus sensitization and culture in asthma are associated with disease severity and lung function impairment, but their relationship with airway inflammation is poorly understood. We investigated the profile of 24 sputum inflammatory mediators in A. fumigatus culture-positive or-negative moderate-to-severe asthmatics. Fifty-two subjects were recruited from a single center. A. fumigatus was cultured from 19 asthmatics. Asthma control, symptom score, lung function, and sputum cell count were not significantly different between the asthmatics with and without a positive A. fumigatus culture. All of the sputum mediators were numerically increased in subjects with a positive versus negative sputum A. fumigatus culture. Sputum TNF-R2 was significantly elevated (P=0.03) and the mediator that best distinguished A. fumigatus culture-positive from culture-negative subjects (receiver-operator characteristic area under the curve 0.66 [95% CI: 0.51 to 0.82, P=0.045]). A. fumigates-positive culture in moderate-to-severe asthma is associated with increased inflammatory sputum mediators.
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Affiliation(s)
- Michael A Ghebre
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity & Inflammation, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Dhananjay Desai
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity & Inflammation, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Amisha Singapuri
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity & Inflammation, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Joanne Woods
- MedImmune Ltd, Milstein Building, Granta Park, Cambridge, UK
| | - Laura Rapley
- MedImmune Ltd, Milstein Building, Granta Park, Cambridge, UK
| | - Suzanne Cohen
- MedImmune Ltd, Milstein Building, Granta Park, Cambridge, UK
| | - Athula Herath
- MedImmune Ltd, Milstein Building, Granta Park, Cambridge, UK
| | - Andrew J Wardlaw
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity & Inflammation, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Catherine H Pashley
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity & Inflammation, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Richard May
- MedImmune Ltd, Milstein Building, Granta Park, Cambridge, UK
| | - Chris E Brightling
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity & Inflammation, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK.
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11
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Liu W, Liu S, Verma M, Zafar I, Good JT, Rollins D, Groshong S, Gorska MM, Martin RJ, Alam R. Mechanism of T H2/T H17-predominant and neutrophilic T H2/T H17-low subtypes of asthma. J Allergy Clin Immunol 2016; 139:1548-1558.e4. [PMID: 27702673 DOI: 10.1016/j.jaci.2016.08.032] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/25/2016] [Accepted: 08/16/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND The mechanism of TH2/TH17-predominant and TH2/TH17-low asthma is unknown. OBJECTIVE We sought to study the immune mechanism of TH2/TH17-predominant and TH2/TH17-low asthma. METHODS In a previously reported cohort of 60 asthmatic patients, 16 patients were immunophenotyped with TH2/TH17-predominant asthma and 22 patients with TH2/TH17-low asthma. We examined bronchoalveolar lavage (BAL) fluid leukocytes, cytokines, mediators, and epithelial cell function for these asthma subgroups. RESULTS Patients with TH2/TH17-predominant asthma had increased IL-1β, IL-6, IL-23, C3a, and serum amyloid A levels in BAL fluid, and these correlated with IL-1β and C3a levels. TH2/TH17 cells expressed higher levels of the IL-1 receptor and phospho-p38 mitogen-activated protein kinase. Anakinra, an IL-1 receptor antagonist protein, inhibited BAL TH2/TH17 cell counts. TH2/TH17-low asthma had 2 distinct subgroups: neutrophilic asthma (45%) and pauci-inflammatory asthma (55%). This contrasted with patients with TH2/TH17-predominant and TH2-predominant asthma, which included neutrophilic asthma in 6% and 0% of patients, respectively. BAL fluid neutrophils strongly correlated with BAL fluid myeloperoxidase, IL-8, IL-1α, IL-6, granulocyte colony-stimulating factor, and GM-CSF levels. Sixty percent of the patients with neutrophilic asthma had a pathogenic microorganism in BAL culture, which suggested a subclinical infection. CONCLUSION We uncovered a critical role for the IL-1β pathway in patients with TH2/TH17-predminant asthma. A subgroup of patients with TH2/TH17-low asthma had neutrophilic asthma and increased BAL fluid IL-1α, IL-6, IL-8, granulocyte colony-stimulating factor, and GM-CSF levels. IL-1α was directly involved in IL-8 production and likely contributed to neutrophilic asthma. Sixty percent of neutrophilic patients had a subclinical infection.
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Affiliation(s)
- Weimin Liu
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo
| | - Sucai Liu
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo
| | - Mukesh Verma
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo
| | - Iram Zafar
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo
| | - James T Good
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo; School of Medicine, University of Colorado Denver, Denver, Colo
| | - Donald Rollins
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo; School of Medicine, University of Colorado Denver, Denver, Colo
| | - Stephen Groshong
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo; School of Medicine, University of Colorado Denver, Denver, Colo
| | - Magdalena M Gorska
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo; School of Medicine, University of Colorado Denver, Denver, Colo
| | - Richard J Martin
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo; School of Medicine, University of Colorado Denver, Denver, Colo
| | - Rafeul Alam
- Department of Medicine, Division of Allergy & Immunology, and Division of Pulmonary and Critical Care Medicine, National Jewish Health, Denver, Colo; School of Medicine, University of Colorado Denver, Denver, Colo.
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12
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Zissler UM, Esser-von Bieren J, Jakwerth CA, Chaker AM, Schmidt-Weber CB. Current and future biomarkers in allergic asthma. Allergy 2016; 71:475-94. [PMID: 26706728 DOI: 10.1111/all.12828] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2015] [Indexed: 12/12/2022]
Abstract
Diagnosis early in life, sensitization, asthma endotypes, monitoring of disease and treatment progression are key motivations for the exploration of biomarkers for allergic rhinitis and allergic asthma. The number of genes related to allergic rhinitis and allergic asthma increases steadily; however, prognostic genes have not yet entered clinical application. We hypothesize that the combination of multiple genes may generate biomarkers with prognostic potential. The current review attempts to group more than 161 different potential biomarkers involved in respiratory inflammation to pave the way for future classifiers. The potential biomarkers are categorized into either epithelial or infiltrate-derived or mixed origin, epithelial biomarkers. Furthermore, surface markers were grouped into cell-type-specific categories. The current literature provides multiple biomarkers for potential asthma endotypes that are related to T-cell phenotypes such as Th1, Th2, Th9, Th17, Th22 and Tregs and their lead cytokines. Eosinophilic and neutrophilic asthma endotypes are also classified by epithelium-derived CCL-26 and osteopontin, respectively. There are currently about 20 epithelium-derived biomarkers exclusively derived from epithelium, which are likely to innovate biomarker panels as they are easy to sample. This article systematically reviews and categorizes genes and collects current evidence that may promote these biomarkers to become part of allergic rhinitis or allergic asthma classifiers with high prognostic value.
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Affiliation(s)
- U. M. Zissler
- Center of Allergy & Environment (ZAUM); Technical University of Munich and Helmholtz Center Munich; German Research Center for Environmental Health member of the German Center for Lung Research (DZL); Munich Germany
| | - J. Esser-von Bieren
- Center of Allergy & Environment (ZAUM); Technical University of Munich and Helmholtz Center Munich; German Research Center for Environmental Health member of the German Center for Lung Research (DZL); Munich Germany
| | - C. A. Jakwerth
- Center of Allergy & Environment (ZAUM); Technical University of Munich and Helmholtz Center Munich; German Research Center for Environmental Health member of the German Center for Lung Research (DZL); Munich Germany
| | - A. M. Chaker
- Center of Allergy & Environment (ZAUM); Technical University of Munich and Helmholtz Center Munich; German Research Center for Environmental Health member of the German Center for Lung Research (DZL); Munich Germany
- Department of Otorhinolaryngology and Head and Neck Surgery; Medical School; Technical University of Munich; Munich Germany
| | - C. B. Schmidt-Weber
- Center of Allergy & Environment (ZAUM); Technical University of Munich and Helmholtz Center Munich; German Research Center for Environmental Health member of the German Center for Lung Research (DZL); Munich Germany
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13
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Saglani S, Lloyd CM. Novel concepts in airway inflammation and remodelling in asthma. Eur Respir J 2015; 46:1796-804. [PMID: 26541520 DOI: 10.1183/13993003.01196-2014] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/25/2015] [Indexed: 02/03/2023]
Abstract
The hallmark pathological features of asthma include airway eosinophilic inflammation and structural changes (remodelling) which are associated with an irreversible loss in lung function that tracks from childhood to adulthood. In parallel with changes in function, pathological abnormalities occur early, during the pre-school years, are established by school age and subsequently remain (even though symptoms may remit for periods during adulthood). Given the equal importance of inflammation and remodelling in asthma pathogenesis, there is a significant disparity in studies undertaken to investigate the contribution of each. The majority focus on the role of inflammation, and although novel therapeutics such as those targeted against T-helper cell type 2 (Th2) mediators have arisen, it is apparent that targeting inflammation alone has not allowed disease modification. Therefore, unless airway remodelling is addressed for future therapeutic strategies, it is unlikely that we will progress towards a cure for asthma. Having acknowledged these limitations, the focus of this review is to highlight the gaps in our current knowledge about the mechanisms underlying airway remodelling, the relationships between remodelling, inflammation and function, remodelling and clinical phenotypes, and the importance of utilising innovative and realistic pre-clinical models to uncover effective, disease-modifying therapeutic strategies.
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Affiliation(s)
- Sejal Saglani
- Inflammation, Repair and Development Section, National Heart & Lung Institute, Imperial College London, London, UK Dept of Respiratory Paediatrics, Royal Brompton Hospital, London, UK
| | - Clare M Lloyd
- Inflammation, Repair and Development Section, National Heart & Lung Institute, Imperial College London, London, UK
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14
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Castanhinha S, Sherburn R, Walker S, Gupta A, Bossley CJ, Buckley J, Ullmann N, Grychtol R, Campbell G, Maglione M, Koo S, Fleming L, Gregory L, Snelgrove RJ, Bush A, Lloyd CM, Saglani S. Pediatric severe asthma with fungal sensitization is mediated by steroid-resistant IL-33. J Allergy Clin Immunol 2015; 136:312-22.e7. [PMID: 25746970 PMCID: PMC4534777 DOI: 10.1016/j.jaci.2015.01.016] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 12/24/2014] [Accepted: 01/05/2015] [Indexed: 11/16/2022]
Abstract
Background The mechanism underlying severe asthma with fungal sensitization (SAFS) is unknown. IL-33 is important in fungus-induced asthma exacerbations, but its role in fungal sensitization is unexplored. Objective We sought to determine whether fungal sensitization in children with severe therapy-resistant asthma is mediated by IL-33. Methods Eighty-two children (median age, 11.7 years; 63% male) with severe therapy-resistant asthma were included. SAFS (n = 38) was defined as specific IgE or skin prick test response positivity to Aspergillus fumigatus, Alternaria alternata, or Cladosporium herbarum. Clinical features and airway immunopathology were assessed. Chronic exposure to house dust mite and A alternata were compared in a neonatal mouse model. Results Children with SAFS had earlier symptom onset (0.5 vs 1.5 years, P = .006), higher total IgE levels (637 vs 177 IU/mL, P = .002), and nonfungal inhalant allergen-specific IgE. Significantly more children with SAFS were prescribed maintenance oral steroids (42% vs 14%, P = .02). SAFS was associated with higher airway IL-33 levels. In neonatal mice A alternata exposure induced higher serum IgE levels, pulmonary IL-33 levels, and IL-13+ innate lymphoid cell (ILC) and TH2 cell numbers but similar airway hyperresponsiveness (AHR) compared with those after house dust mite exposure. Lung IL-33 levels, IL-13+ ILC numbers, TH2 cell numbers, IL-13 levels, and AHR remained increased with inhaled budesonide during A alternata exposure, but all features were significantly reduced in ST2−/− mice lacking a functional receptor for IL-33. Conclusion Pediatric SAFS was associated with more oral steroid therapy and higher IL-33 levels. A alternata exposure resulted in increased IL-33–mediated ILC2 numbers, TH2 cell numbers, and steroid-resistant AHR. IL-33 might be a novel therapeutic target for SAFS.
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Affiliation(s)
- Susana Castanhinha
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom
| | - Rebekah Sherburn
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Simone Walker
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Atul Gupta
- Department of Respiratory Paediatrics, Kings College Hospital, London, United Kingdom
| | - Cara J Bossley
- Department of Respiratory Paediatrics, Kings College Hospital, London, United Kingdom
| | - James Buckley
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Nicola Ullmann
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom
| | - Ruth Grychtol
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Gaynor Campbell
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Marco Maglione
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom
| | - Sergio Koo
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom
| | - Louise Fleming
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom; Airways Disease, NHLI, Imperial College London, London, United Kingdom
| | - Lisa Gregory
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Robert J Snelgrove
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Andrew Bush
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom; Airways Disease, NHLI, Imperial College London, London, United Kingdom
| | - Clare M Lloyd
- Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom
| | - Sejal Saglani
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, United Kingdom; Leukocyte Biology, NHLI, Imperial College London, London, United Kingdom.
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15
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Persson C. Primary lysis of eosinophils in severe desquamative asthma. Clin Exp Allergy 2014; 44:173-83. [PMID: 24330324 DOI: 10.1111/cea.12255] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Primary lysis of eosinophils liberates free eosinophil granules (FEGs) releasing toxic proteins in association with bronchial epithelial injury repair. Eosinophil lysis may be significantly pathogenic. Bronchial mucosal FEGs are associated with uncontrolled asthma, severe asthma, aspirin-sensitive asthma, and lethal asthma. FEGs in the bronchial wall may characterize severe asthma without sputum eosinophilia. Excessive numbers of sputum FEGs occur in severe exacerbations of asthma and are reduced along with clinical improvement. Occurrence of FEGs affects interpretation of other sputum biomarkers including numbers of eosinophils, ECP, and eosinophil-stained macrophages. Thus, eosinophil lysis produces FEGs as bronchial biomarkers of severe asthma. Blood eosinophils in severe asthma seem primed exhibiting a propensity to lyse that is greater the more severe the asthma. Proclivity of blood eosinophils to lyse also distinguished three levels of severity among children with exacerbations of asthma. Numerous FEGs releasing toxic proteins occur in association with grave derangement and shedding of epithelium in severe asthma. Subepithelial FEGs correlate negatively with intact bronchial epithelium in clinically uncontrolled asthma. Significant correlations between sputum ECP, Creola bodies, and severity of asthma exacerbations have also been demonstrated. Hence, eosinophil lysis apparently causes epithelial desquamation in severe asthma. Exaggerated epithelial repair in turn would contribute to inflammatory and remodelling features of severe asthma. Perseverance of FEGs together with maintained disease activity, despite treatment with 'eosinophil-depleting' steroids and anti-IL5 biologicals, agrees with the possibility that eosinophil lysis is worthy target for novel anti-asthma drugs. Priming and lysis of eosinophils, and protein release from FEGs, are regulated and can be targeted. Eosinophil lysis and FEGs belong to the disease picture of severe asthma and need consideration in asthma studies concerned with phenotypes, biomarkers, roles of epithelial injury/repair, and targeting novel drugs.
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Affiliation(s)
- C Persson
- Laboratory Medicine, Lund University Hospital, Lund, Sweden
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16
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Singh SR, Sutcliffe A, Kaur D, Gupta S, Desai D, Saunders R, Brightling CE. CCL2 release by airway smooth muscle is increased in asthma and promotes fibrocyte migration. Allergy 2014; 69:1189-97. [PMID: 24931417 PMCID: PMC4215601 DOI: 10.1111/all.12444] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND Asthma is characterized by variable airflow obstruction, airway inflammation, airway hyper-responsiveness and airway remodelling. Airway smooth muscle (ASM) hyperplasia is a feature of airway remodelling and contributes to bronchial wall thickening. We sought to investigate the expression levels of chemokines in primary cultures of ASM cells from asthmatics vs healthy controls and to assess whether differentially expressed chemokines (i) promote fibrocyte (FC) migration towards ASM and (ii) are increased in blood from subjects with asthma and in sputum samples from those asthmatics with bronchial wall thickening. METHODS Chemokine concentrations released by primary ASM were measured by MesoScale Discovery platform. The chemokine most highly expressed by ASM from asthmatics compared with healthy controls was confirmed by ELISA, and expression of its cognate chemokine receptor by FCs was examined by immunofluorescence and flow cytometry. The role of this chemokine in FC migration towards ASM was investigated by chemotaxis assays. RESULTS Chemokine (C-C motif) ligand 2 (CCL2) levels were increased in primary ASM supernatants from asthmatics compared with healthy controls. CCR2 was expressed on FCs. Fibrocytes migrated towards recombinant CCL2 and ASM supernatants. These effects were inhibited by CCL2 neutralization. CCL2 levels were increased in blood from asthmatics compared with healthy controls, and sputum CCL2 was increased in asthmatics with bronchial wall thickening. CONCLUSIONS Airway smooth muscle-derived CCL2 mediates FC migration and potentially contributes to the development of ASM hyperplasia in asthma.
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Affiliation(s)
- S R Singh
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
| | - A Sutcliffe
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
| | - D Kaur
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
| | - S Gupta
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
| | - D Desai
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
| | - R Saunders
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
| | - C E Brightling
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, UK
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