1
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Ben-Meir E, Perrem L, Shaw M, Ratjen F, Grasemann H. SPLUNC1 as a biomarker of pulmonary exacerbations in children with cystic fibrosis. J Cyst Fibros 2024; 23:288-292. [PMID: 38413298 DOI: 10.1016/j.jcf.2024.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/14/2024] [Accepted: 02/19/2024] [Indexed: 02/29/2024]
Abstract
BACKGROUND Short palate, lung, and nasal epithelium clone 1 (SPLUNC1) is an innate defence protein that acts as an anti-microbial agent and regulates airway surface liquid volume through inhibition of the epithelial sodium channel (ENaC). SPLUNC1 levels were found to be reduced in airway secretions of adults with cystic fibrosis (CF). The potential of SPLUNC1 as a biomarker in children with CF is unknown. METHODS We quantified SPLUNC1, interleukin-8 (IL-8) and neutrophil elastase (NE) in sputum of CF children treated with either intravenous antibiotics or oral antibiotics for a pulmonary exacerbation (PEx)s, and in participants of a prospective cohort of CF children with preserved lung function on spirometry, followed over a period of two years. RESULTS Sputum SPLUNC1 levels were significantly lower before compared to after intravenous and oral antibiotic therapy for PEx. In the longitudinal cohort, SPLUNC1 levels were found to be decreased at PEx visits compared to both previous and subsequent stable visits. Higher SPLUNC1 levels at stable visits were associated with longer PEx-free time (hazard ratio 0.85, p = 0.04). SPLUNC1 at PEx visits did not correlate with IL-8 or NE levels in sputum or forced expiratory volume in one second (FEV1) but did correlate with the lung clearance index (LCI) (r=-0.53, p < 0.001). CONCLUSION SPLUNC1 demonstrates promising clinometric properties as a biomarker of PEx in children with CF.
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Affiliation(s)
- E Ben-Meir
- Division of Respiratory Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Canada; Translational Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; University of Toronto, Toronto, Ontario, Canada
| | - L Perrem
- Division of Respiratory Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Canada; Translational Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; University of Toronto, Toronto, Ontario, Canada
| | - M Shaw
- Division of Respiratory Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Canada; Translational Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - F Ratjen
- Division of Respiratory Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Canada; Translational Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; University of Toronto, Toronto, Ontario, Canada
| | - H Grasemann
- Division of Respiratory Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Canada; Translational Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; University of Toronto, Toronto, Ontario, Canada.
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2
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Iannuzo N, Welfley H, Li NC, Johnson MDL, Rojas-Quintero J, Polverino F, Guerra S, Li X, Cusanovich DA, Langlais PR, Ledford JG. CC16 drives VLA-2-dependent SPLUNC1 expression. Front Immunol 2023; 14:1277582. [PMID: 38053993 PMCID: PMC10694244 DOI: 10.3389/fimmu.2023.1277582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 10/30/2023] [Indexed: 12/07/2023] Open
Abstract
Rationale CC16 (Club Cell Secretory Protein) is a protein produced by club cells and other non-ciliated epithelial cells within the lungs. CC16 has been shown to protect against the development of obstructive lung diseases and attenuate pulmonary pathogen burden. Despite recent advances in understanding CC16 effects in circulation, the biological mechanisms of CC16 in pulmonary epithelial responses have not been elucidated. Objectives We sought to determine if CC16 deficiency impairs epithelial-driven host responses and identify novel receptors expressed within the pulmonary epithelium through which CC16 imparts activity. Methods We utilized mass spectrometry and quantitative proteomics to investigate how CC16 deficiency impacts apically secreted pulmonary epithelial proteins. Mouse tracheal epithelial cells (MTECS), human nasal epithelial cells (HNECs) and mice were studied in naïve conditions and after Mp challenge. Measurements and main results We identified 8 antimicrobial proteins significantly decreased by CC16-/- MTECS, 6 of which were validated by mRNA expression in Severe Asthma Research Program (SARP) cohorts. Short Palate Lung and Nasal Epithelial Clone 1 (SPLUNC1) was the most differentially expressed protein (66-fold) and was the focus of this study. Using a combination of MTECs and HNECs, we found that CC16 enhances pulmonary epithelial-driven SPLUNC1 expression via signaling through the receptor complex Very Late Antigen-2 (VLA-2) and that rCC16 given to mice enhances pulmonary SPLUNC1 production and decreases Mycoplasma pneumoniae (Mp) burden. Likewise, rSPLUNC1 results in decreased Mp burden in mice lacking CC16 mice. The VLA-2 integrin binding site within rCC16 is necessary for induction of SPLUNC1 and the reduction in Mp burden. Conclusion Our findings demonstrate a novel role for CC16 in epithelial-driven host defense by up-regulating antimicrobials and define a novel epithelial receptor for CC16, VLA-2, through which signaling is necessary for enhanced SPLUNC1 production.
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Affiliation(s)
- Natalie Iannuzo
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ, United States
| | - Holly Welfley
- Asthma and Airway Disease Research Center, Tucson, AZ, United States
| | | | | | | | | | - Stefano Guerra
- Asthma and Airway Disease Research Center, Tucson, AZ, United States
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona, Tucson, AZ, United States
| | - Xingnan Li
- Department of Medicine, Division of Genetics, Genomics, and Precision Medicine, University of Arizona, Tucson, AZ, United States
| | - Darren A. Cusanovich
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ, United States
- Asthma and Airway Disease Research Center, Tucson, AZ, United States
| | - Paul R. Langlais
- Department of Medicine, Division of Endocrinology, University of Arizona, Tucson, AZ, United States
| | - Julie G. Ledford
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ, United States
- Asthma and Airway Disease Research Center, Tucson, AZ, United States
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3
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Li X, Xiao S, Filipczak N, Yalamarty SSK, Shang H, Zhang J, Zheng Q. Role and Therapeutic Targeting Strategies of Neutrophil Extracellular Traps in Inflammation. Int J Nanomedicine 2023; 18:5265-5287. [PMID: 37746050 PMCID: PMC10516212 DOI: 10.2147/ijn.s418259] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 08/29/2023] [Indexed: 09/26/2023] Open
Abstract
Neutrophil extracellular traps (NETs) are large DNA reticular structures secreted by neutrophils and decorated with histones and antimicrobial proteins. As a key mechanism for neutrophils to resist microbial invasion, NETs play an important role in the killing of microorganisms (bacteria, fungi, and viruses). Although NETs are mostly known for mediating microbial killing, increasing evidence suggests that excessive NETs induced by stimulation of physical and chemical components, microorganisms, and pathological factors can exacerbate inflammation and organ damage. This review summarizes the induction and role of NETs in inflammation and focuses on the strategies of inhibiting NETosis and the mechanisms involved in pathogen evasion of NETs. Furthermore, herbal medicine inhibitors and nanodelivery strategies improve the efficiency of inhibition of excessive levels of NETs.
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Affiliation(s)
- Xiang Li
- National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine, Jiangxi University of Chinese Medicine, Nanchang, Jiangxi, People’s Republic of China
| | - Shanghua Xiao
- Key Laboratory of Modern Preparation of TCM, Ministry of Education, Jiangxi University of Chinese Medicine, Nanchang, Jiangxi, People’s Republic of China
| | - Nina Filipczak
- Center for Pharmaceutical Biotechnology and Nanomedicine, Northeastern University, Boston, MA, USA
| | | | - Hongming Shang
- Department of Biochemistry & Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - Jing Zhang
- Key Laboratory of Modern Preparation of TCM, Ministry of Education, Jiangxi University of Chinese Medicine, Nanchang, Jiangxi, People’s Republic of China
| | - Qin Zheng
- Key Laboratory of Modern Preparation of TCM, Ministry of Education, Jiangxi University of Chinese Medicine, Nanchang, Jiangxi, People’s Republic of China
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4
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Roszkowiak J, McClean S, Mirończuk AM, Augustyniak D. The Direct Anti-Virulence but Not Bactericidal Activity of Human Neutrophil Elastase against Moraxella catarrhalis. Int J Mol Sci 2023; 24:ijms24076607. [PMID: 37047578 PMCID: PMC10094786 DOI: 10.3390/ijms24076607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/18/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
Neutrophil elastase (NE) contributes to innate antibacterial defense at both the intracellular (phagocytosis) and extracellular (degranulation, NETosis) levels. Moraxella catarrhalis, a human respiratory pathogen, can exist in an inflammatory milieu which contains NE. No data are available on the action of NE against M. catarrhalis or on the counteraction of NE-dependent host defenses by this pathogen. Using time-kill assays we found that bacteria are able to survive and replicate in the presence of NE. Transmission electron microscopy and flow cytometry studies with NE-treated bacteria revealed that while NE admittedly destabilizes the outer membrane leaflet, it does not cause cytoplasmic membrane rupture, suggesting that the enzyme does not target components that are essential for cell integrity. Using LC-MS/MS spectroscopy we determined that NE cleaved at least three virulent surface proteins in outer membrane vesicles (OMVs) of M. catarrhalis, including OMP CD, McaP, and TbpA. The cleavage of OMP CD contributes to the significant decrease in resistance to serum complement in the complement-resistant strain Mc6. The cleavage of McaP did not cause any sensitization to erythromycin nor did NE disturb its drug action. Identifying NE as a novel but subtle anti-virulence agent together with its extracellularly not-efficient bactericidal activity against M. catarrhalis may facilitate the pathogen’s existence in the airways under inflammation.
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Affiliation(s)
- Justyna Roszkowiak
- Department of Pathogen Biology and Immunology, Faculty of Biological Sciences, University of Wroclaw, 51-148 Wroclaw, Poland
| | - Siobhán McClean
- School of Biomolecular and Biomedical Sciences and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, D04 V1W8 Dublin, Ireland
| | - Aleksandra M. Mirończuk
- Laboratory for Biosustainability, Institute of Environmental Biology, Wroclaw University of Environmental and Life Sciences, 51-631 Wroclaw, Poland
| | - Daria Augustyniak
- Department of Pathogen Biology and Immunology, Faculty of Biological Sciences, University of Wroclaw, 51-148 Wroclaw, Poland
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5
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Wu T, Goriounova AS, Worthington EN, Wrennall JA, Ghosh A, Ahmad S, Flori Sassano M, Tarran R. SPLUNC1 is a negative regulator of the Orai1 Ca 2+ channel. Physiol Rep 2022; 10:e15306. [PMID: 35581745 PMCID: PMC9114653 DOI: 10.14814/phy2.15306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 04/22/2022] [Accepted: 04/27/2022] [Indexed: 06/15/2023] Open
Abstract
Orai1 is a ubiquitously-expressed plasma membrane Ca2+ channel that is involved in store-operated Ca2+ entry (SOCE): a fundamental biological process that regulates gene expression, the onset of inflammation, secretion, and the contraction of airway smooth muscle (ASM). During SOCE, Ca2+ leaves the endoplasmic reticulum, which then stimulates a second, amplifying wave of Ca2+ influx through Orai1 into the cytoplasm. Short Palate LUng and Nasal epithelial Clone 1 (SPLUNC1; gene name BPIFA1) is a multi-functional, innate defense protein that is highly abundant in the lung. We have previously reported that SPLUNC1 was secreted from epithelia, where it bound to and inhibited Orai1, leading to reduced SOCE and ASM relaxation. However, the underlying mechanism of action is unknown. Here, we probed the SPLUNC1-Orai1 interactions in ASM and HEK293T cells using biochemical and imaging techniques. We observed that SPLUNC1 caused a conformational change in Orai1, as measured using Forster resonance energy transfer (FRET). SPLUNC1 binding also led to Nedd4-2 dependent ubiquitination of Orai1. Moreover, SPLUNC1 internalized Orai1 to lysosomes, leading to Orai1 degradation. Thus, we conclude that SPLUNC1 is an allosteric regulator of Orai1. Our data indicate that SPLUNC1-mediated Orai1 inhibition could be utilized as a therapeutic strategy to reduce SOCE.
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Affiliation(s)
- Tongde Wu
- Department of Cell Biology & PhysiologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
| | - Alexandra S. Goriounova
- Department of PharmacologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
| | - Erin N. Worthington
- Divison of PulmonologyDepartment of PediatricsThe University of North Carolina at Chapel HillNorth Carolina27599USA
- Division of Pulmonology, Department of PediatricsCarilion Clinic and Virginia Tech Carilion School of MedicineRoanokeVirginia24016USA
| | - Joe A. Wrennall
- Department of Cell Biology & PhysiologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
| | - Arunava Ghosh
- Department of Cell Biology & PhysiologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
| | - Saira Ahmad
- Department of Cell Biology & PhysiologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
| | - M. Flori Sassano
- Department of Cell Biology & PhysiologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
| | - Robert Tarran
- Department of Cell Biology & PhysiologyThe University of North Carolina at Chapel HillNorth Carolina27599USA
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6
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Keir HR, Chalmers JD. Neutrophil extracellular traps in chronic lung disease: implications for pathogenesis and therapy. Eur Respir Rev 2022; 31:31/163/210241. [PMID: 35197267 PMCID: PMC9488971 DOI: 10.1183/16000617.0241-2021] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/28/2021] [Indexed: 12/20/2022] Open
Abstract
Neutrophilic inflammation has a key role in the pathophysiology of multiple chronic lung diseases. The formation of neutrophil extracellular traps (NETs) has emerged as a key mechanism of disease in neutrophilic lung diseases including asthma, COPD, cystic fibrosis and, most recently, bronchiectasis. NETs are large, web-like structures composed of DNA and anti-microbial proteins that are able to bind pathogens, prevent microbial dissemination and degrade bacterial virulence factors. The release of excess concentrations of proteases, antimicrobial proteins, DNA and histones, however, also leads to tissue damage, impaired mucociliary clearance, impaired bacterial killing and increased inflammation. A number of studies have linked airway NET formation with greater disease severity, increased exacerbations and overall worse disease outcomes across the spectrum of airway diseases. Treating neutrophilic inflammation has been challenging in chronic lung disease because of the delicate balance between reducing inflammation and increasing the risk of infections through immunosuppression. Novel approaches to suppressing NET formation or the associated inflammation are in development and represent an important therapeutic target. This review will discuss the relationship between NETs and the pathophysiology of cystic fibrosis, asthma, COPD and bronchiectasis, and explore the current and future development of NET-targeting therapies. NETs contribute to the pathophysiology of chronic lung disease. Immunomodulating therapies that may reduce inflammatory mediators and NET formation, without compromising bacterial clearance, offer a new treatment path for patients. https://bit.ly/3fyJC6I
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Affiliation(s)
- Holly R Keir
- Division of Molecular and Clinical Medicine, Ninewells Hospital and Medical School, Dundee, UK
| | - James D Chalmers
- Division of Molecular and Clinical Medicine, Ninewells Hospital and Medical School, Dundee, UK
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7
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Bingle CD, Bingle L. SPLUNC1 comes of age? Predicting acute exacerbations in cystic fibrosis. Eur Respir J 2021; 58:58/5/2101569. [PMID: 34764214 DOI: 10.1183/13993003.01569-2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 11/05/2022]
Affiliation(s)
- Colin D Bingle
- Dept of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Lynne Bingle
- Academic Unit of Oral and Maxillofacial Pathology, School of Clinical Dentistry, University of Sheffield, Sheffield, UK
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8
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Hanssens LS, Duchateau J, Casimir GJ. CFTR Protein: Not Just a Chloride Channel? Cells 2021; 10:2844. [PMID: 34831067 PMCID: PMC8616376 DOI: 10.3390/cells10112844] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/17/2022] Open
Abstract
Cystic fibrosis (CF) is a recessive genetic disease caused by mutations in a gene encoding a protein called Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). The CFTR protein is known to acts as a chloride (Cl-) channel expressed in the exocrine glands of several body systems where it also regulates other ion channels, including the epithelial sodium (Na+) channel (ENaC) that plays a key role in salt absorption. This function is crucial to the osmotic balance of the mucus and its viscosity. However, the pathophysiology of CF is more challenging than a mere dysregulation of epithelial ion transport, mainly resulting in impaired mucociliary clearance (MCC) with consecutive bronchiectasis and in exocrine pancreatic insufficiency. This review shows that the CFTR protein is not just a chloride channel. For a long time, research in CF has focused on abnormal Cl- and Na+ transport. Yet, the CFTR protein also regulates numerous other pathways, such as the transport of HCO3-, glutathione and thiocyanate, immune cells, and the metabolism of lipids. It influences the pH homeostasis of airway surface liquid and thus the MCC as well as innate immunity leading to chronic infection and inflammation, all of which are considered as key pathophysiological characteristics of CF.
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Affiliation(s)
- Laurence S. Hanssens
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
| | - Jean Duchateau
- Laboratoire Académique de Pédiatrie, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
| | - Georges J. Casimir
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
- Laboratoire Académique de Pédiatrie, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
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9
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Khanal S, Webster M, Niu N, Zielonka J, Nunez M, Chupp G, Slade MD, Cohn L, Sauler M, Gomez JL, Tarran R, Sharma L, Dela Cruz CS, Egan M, Laguna T, Britto CJ. SPLUNC1: a novel marker of cystic fibrosis exacerbations. Eur Respir J 2021; 58:13993003.00507-2020. [PMID: 33958427 DOI: 10.1183/13993003.00507-2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 03/29/2021] [Indexed: 11/05/2022]
Abstract
Acute pulmonary Exacerbations (AE) are episodes of clinical worsening in cystic fibrosis (CF), often precipitated by infection. Timely detection is critical to minimise morbidity and lung function declines associated with acute inflammation during AE. Based on our previous observations that airway protein Short Palate Lung Nasal epithelium Clone 1 (SPLUNC1) is regulated by inflammatory signals, we investigated the use of SPLUNC1 fluctuations to diagnose and predict AE in CF.We enrolled CF participants from two independent cohorts to measure AE markers of inflammation in sputum and recorded clinical outcomes for a 1-year follow-up period.SPLUNC1 levels were high in healthy controls (n=9, 10.7 μg mL-1), and significantly decreased in CF participants without AE (n=30, 5.7 μg mL-1, p=0.016). SPLUNC1 levels were 71.9% lower during AE (n=14, 1.6 μg mL-1, p=0.0034) regardless of age, sex, CF-causing mutation, or microbiology findings. Cytokines Il-1β and TNFα were also increased in AE, whereas lung function did not consistently decrease. Stable CF participants with lower SPLUNC1 levels were much more likely to have an AE at 60 days (HR: 11.49, Standard Error: 0.83, p=0.0033). Low-SPLUNC1 stable participants remained at higher AE risk even one year after sputum collection (HR: 3.21, Standard Error: 0.47, p=0.0125). SPLUNC1 was downregulated by inflammatory cytokines and proteases increased in sputum during AE.In acute CF care, low SPLUNC1 levels could support a decision to increase airway clearance or to initiate pharmacological interventions. In asymptomatic, stable patients, low SPLUNC1 levels could inform changes in clinical management to improve long-term disease control and clinical outcomes in CF.
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Affiliation(s)
- Sara Khanal
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Megan Webster
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Naiqian Niu
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Jana Zielonka
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Myra Nunez
- Division of Pediatric Respiratory Medicine, University of Minnesota, Minneapolis, Minnesota, USA
| | - Geoffrey Chupp
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Martin D Slade
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Lauren Cohn
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Maor Sauler
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Jose L Gomez
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Robert Tarran
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Lokesh Sharma
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Charles S Dela Cruz
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Marie Egan
- Division of Pediatric Pulmonology, Allergy, Immunology, and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Theresa Laguna
- Division of Pediatric Respiratory Medicine, University of Minnesota, Minneapolis, Minnesota, USA
| | - Clemente J Britto
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
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10
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Liu Q, Wang Z, Zhang W. The Multifunctional Roles of Short Palate, Lung, and Nasal Epithelium Clone 1 in Regulating Airway Surface Liquid and Participating in Airway Host Defense. J Interferon Cytokine Res 2021; 41:139-148. [PMID: 33885339 DOI: 10.1089/jir.2020.0141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Short palate, lung, and nasal epithelium clone 1 (SPLUNC1) is a kind of secretory protein, and gets expressed abundantly in normal respiratory epithelium of humans. As a natural immune molecule, SPLUNC1 is proved to be involved in inflammatory response and airway host defense. This review focuses on summarizing and discussing the role of SPLUNC1 in regulating airway surface liquid (ASL) and participating in airway host defense. PubMed and MEDLINE were used for searching and identifying the data in this review. The domain of bactericidal/permeability-increasing protein in SPLUNC1 and the α-helix, α4, are essential for SPLUNC1 to exert biological activities. As a natural innate immune molecule, SPLUNC1 plays a significant role in inflammatory response and airway host defense. Its special expression patterns are not only observed in physiological conditions, but also in some respiratory diseases. The mechanisms of SPLUNC1 in airway host defense include modulating ASL volume, acting as a surfactant protein, inhibiting biofilm formation, as well as regulating ASL compositions, such as LL-37, mucins, Neutrophil elastase, and inflammatory cytokines. Besides, potential correlations are found among these different mechanisms, especially among different ASL compositions, which should be further explored in more systematical frameworks. In this review, we summarize the structural characteristics and expression patterns of SPLUNC1 briefly, and mainly discuss the mechanisms of SPLUNC1 exerted in host defense, aiming to provide a theoretical basis and a novel target for future studies and clinical treatments.
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Affiliation(s)
- Qingluan Liu
- Department of Medical Laboratory Science, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhicheng Wang
- Department of Medical Laboratory Science, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wenling Zhang
- Department of Medical Laboratory Science, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
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11
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Rouadi PW, Idriss SA, Naclerio RM, Peden DB, Ansotegui IJ, Canonica GW, Gonzalez-Diaz SN, Rosario Filho NA, Ivancevich JC, Hellings PW, Murrieta-Aguttes M, Zaitoun FH, Irani C, Karam MR, Bousquet J. Immunopathological features of air pollution and its impact on inflammatory airway diseases (IAD). World Allergy Organ J 2020; 13:100467. [PMID: 33042360 PMCID: PMC7534666 DOI: 10.1016/j.waojou.2020.100467] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/31/2020] [Accepted: 09/11/2020] [Indexed: 12/14/2022] Open
Abstract
Air pollution causes significant morbidity and mortality in patients with inflammatory airway diseases (IAD) such as allergic rhinitis (AR), chronic rhinosinusitis (CRS), asthma, and chronic obstructive pulmonary disease (COPD). Oxidative stress in patients with IAD can induce eosinophilic inflammation in the airways, augment atopic allergic sensitization, and increase susceptibility to infection. We reviewed emerging data depicting the involvement of oxidative stress in IAD patients. We evaluated biomarkers, outcome measures and immunopathological alterations across the airway mucosal barrier following exposure, particularly when accentuated by an infectious insult.
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Key Words
- AR, Allergic rhinitis
- Air pollution
- Antioxidant
- COPD, Chronic obstructive pulmonary disease
- CRS, Chronic rhinosinusitis
- DEP, Diesel exhaust particles
- IAD, Inflammatory airway diseases
- IL, Interleukin
- ILC, Innate lymphoid cells
- Inflammatory airway disease
- NOx, Nitrogen oxides
- Oxidative stress biomarkers
- PAH, Polycyclic aromatic hydrocarbons
- PM, Particulate matter
- ROS, Reactive oxygen species
- TBS, Tobacco smoke
- TLR, Toll-like receptors
- Tobacco smoke
- Treg, Regulatory T cell
- VOCs, Volatile organic compounds
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Affiliation(s)
- Philip W. Rouadi
- Department of Otolaryngology-Head and Neck Surgery, Eye and Ear University Hospital, Beirut, Lebanon
| | - Samar A. Idriss
- Department of Otolaryngology-Head and Neck Surgery, Eye and Ear University Hospital, Beirut, Lebanon
| | - Robert M. Naclerio
- Johns Hopkins University Department of Otolaryngology - Head and Neck Surgery, Baltimore, MD, USA
| | - David B. Peden
- UNC Center for Environmental Medicine, Asthma, and Lung Biology, Division of Allergy, Immunology and Rheumatology, Department of Pediatrics UNS School of Medicine, USA
| | - Ignacio J. Ansotegui
- Department of Allergy and Immunology, Hospital Quironsalud Bizkaia, Bilbao, Spain
| | | | - Sandra Nora Gonzalez-Diaz
- University Autonoma de Nuevo Leon Facultad de Medicina y Hospital Universitario U.A.N.L, Monterrey, NL, c.p. 64460, México
| | | | - Juan Carlos Ivancevich
- Faculty of Medicine, Universidad del Salvador, Buenos Aires, Argentina and Head of Allergy and Immunology at the Santa Isabel Clinic, Buenos Aires, Argentina
| | - Peter W. Hellings
- Department of Otorhinolaryngology, University Hospitals Leuven, Leuven, Belgium
- Department of Otorhinolaryngology, Academic Medical Center Amsterdam, The Netherlands - Department Otorhinolaryngology, University Hospital Ghent, Belgium
| | | | - Fares H. Zaitoun
- LAUMC Rizk Hospital, Otolaryngology-Allergy Department, Beirut, Lebanon
| | - Carla Irani
- Department of Internal Medicine and Infectious Diseases, St Joseph University, Hotel Dieu de France Hospital, Beirut, Lebanon
| | - Marilyn R. Karam
- Division of Rheumatology, Allergy and Clinical Immunology, Department of Internal Medicine, American University of Beirut, Beirut, Lebanon
| | - Jean Bousquet
- INSERM U 1168, VIMA: Ageing and Chronic Diseases Epidemiological and Public Health Approaches, Villejuif, France
- University Versailles St-Quentin-en-Yvelines, France
- Allergy-Centre-Charité, Charité–Universitätsmedizin Berlin, Berlin, Germany
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12
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Zhang R, Trower J, Wu T. Degradation of bacterial permeability family member A1 (BPIFA1) by house dust mite (HDM) cysteine protease Der p 1 abrogates immune modulator function. Int J Biol Macromol 2020; 164:4022-4031. [PMID: 32890564 PMCID: PMC7467078 DOI: 10.1016/j.ijbiomac.2020.08.214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 08/19/2020] [Accepted: 08/28/2020] [Indexed: 01/01/2023]
Abstract
Bacterial permeability family member A1 (BPIFA1) is one of the most abundant proteins present in normal airway surface liquid (ASL). It is known to be diminished in asthmatic patients' sputum, which causes airway hyperresponsiveness (AHR). What is currently unclear is how environmental factors, such as allergens' impact on BPIFA1's abundance and functions in the context of allergic asthma. House dust mite (HDM) is a predominant domestic source of aeroallergens. The group of proteases found in HDM is thought to cleave multiple cellular protective mechanisms, and therefore foster the development of allergic asthma. Here, we show that BPIFA1 is cleaved by HDM proteases in a time-, dose-, and temperature-dependent manner. We have also shown the main component in HDM that is responsible for BPIFA1's degradation is Der p1. Fragmented BPIFA1 failed to bind E. coli lipopolysaccharide (LPS), and hence elevated TNFα and IL-6 secretion in human whole blood. BPIFA1 degradation is also observed in vivo in bronchoalveolar fluid (BALF) of mice which are intranasally instilled with HDM. These data suggest that proteases associated with environmental allergens such as HDM cleave BPIFA1 and therefore impair its immune modulator function.
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Affiliation(s)
- Rui Zhang
- Department of Respiratory and Critical Care Medicine, General Hospital of Ningxia Medical University, Ningxia Medical University, Yinchuan, PR China
| | - Jessika Trower
- Department of Pharmaceutical Sciences, 302 East Lawson Street, North Carolina Central University, Durham, NC 27707, USA
| | - Tongde Wu
- Department of Pharmaceutical Sciences, 302 East Lawson Street, North Carolina Central University, Durham, NC 27707, USA; Biomanufacturing Research Institute & Technology Enterprise (BRITE), 302 East Lawson Street, North Carolina Central University, Durham, NC 27707, USA.
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13
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Guo-Parke H, Linden D, Weldon S, Kidney JC, Taggart CC. Mechanisms of Virus-Induced Airway Immunity Dysfunction in the Pathogenesis of COPD Disease, Progression, and Exacerbation. Front Immunol 2020; 11:1205. [PMID: 32655557 PMCID: PMC7325903 DOI: 10.3389/fimmu.2020.01205] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 05/14/2020] [Indexed: 12/21/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is the integrated form of chronic obstructive bronchitis and pulmonary emphysema, characterized by persistent small airway inflammation and progressive irreversible airflow limitation. COPD is characterized by acute pulmonary exacerbations and associated accelerated lung function decline, hospitalization, readmission and an increased risk of mortality, leading to huge social-economic burdens. Recent evidence suggests ~50% of COPD acute exacerbations are connected with a range of respiratory viral infections. Nevertheless, respiratory viral infections have been linked to the severity and frequency of exacerbations and virus-induced secondary bacterial infections often result in a synergistic decline of lung function and longer hospitalization. Here, we review current advances in understanding the cellular and molecular mechanisms underlying the pathogenesis of COPD and the increased susceptibility to virus-induced exacerbations and associated immune dysfunction in patients with COPD. The multiple immune regulators and inflammatory signaling pathways known to be involved in host-virus responses are discussed. As respiratory viruses primarily target airway epithelial cells, virus-induced inflammatory responses in airway epithelium are of particular focus. Targeting virus-induced inflammatory pathways in airway epithelial cells such as Toll like receptors (TLRs), interferons, inflammasomes, or direct blockade of virus entry and replication may represent attractive future therapeutic targets with improved efficacy. Elucidation of the cellular and molecular mechanisms of virus infections in COPD pathogenesis will undoubtedly facilitate the development of these potential novel therapies that may attenuate the relentless progression of this heterogeneous and complex disease and reduce morbidity and mortality.
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Affiliation(s)
- Hong Guo-Parke
- Airway Innate Immunity Research Group, Wellcome Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Sciences, Queens University Belfast, Belfast, United Kingdom
| | - Dermot Linden
- Airway Innate Immunity Research Group, Wellcome Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Sciences, Queens University Belfast, Belfast, United Kingdom
| | - Sinéad Weldon
- Airway Innate Immunity Research Group, Wellcome Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Sciences, Queens University Belfast, Belfast, United Kingdom
| | - Joseph C Kidney
- Department of Respiratory Medicine Mater Hospital Belfast, Belfast, United Kingdom
| | - Clifford C Taggart
- Airway Innate Immunity Research Group, Wellcome Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Sciences, Queens University Belfast, Belfast, United Kingdom
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14
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Sharma L, Feng J, Britto CJ, Dela Cruz CS. Mechanisms of Epithelial Immunity Evasion by Respiratory Bacterial Pathogens. Front Immunol 2020. [PMID: 32117248 DOI: 10.3389/fimmu.2020.00091/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Bacterial lung infections are major healthcare challenges killing millions of people worldwide and resulting in a huge economic burden. Both basic and clinical research have elucidated host mechanisms that contribute to the bacterial clearance where an indispensable role of immune cells has been established. However, the role of respiratory epithelial cells in bacterial clearance has garnered limited attention due to their weak inflammatory or phagocytic ability compared to immune cells such as macrophages and neutrophils. These studies often underappreciate the fact that epithelial cells are the most abundant cells in the lung, not only serving as building blocks but also providing immune protection throughout the lung. Epithelial cells function either independently to eradicate the pathogen or communicate with immune cells to orchestrate pathogen clearance. The epithelial cells have multiple mechanisms that include mucus production, antimicrobial peptide production, muco-ciliary clearance, and phagocytosis, all of which contribute to their direct antibacterial function. Secretion of cytokines to recruit immune cells and potentiate their antimicrobial activities is a pathway by which the epithelium contributes to bacterial clearance. Successful pathogens outsmart epithelial resistance and find a way to replicate in sufficient numbers to establish infections in the airway or lung epithelial surfaces. In this mini-review, we discuss evidences that establish important roles for epithelial host defense against invading respiratory bacterial pathogens and demonstrate how pathogens outsmart these epithelial immune mechanisms to successfully establish infection. Finally, we discuss briefly how to boost epithelial immunity to improve outcomes in bacterial lung infections.
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Affiliation(s)
- Lokesh Sharma
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Jingjing Feng
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States.,Department of Respiratory Medicine, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Clemente J Britto
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Charles S Dela Cruz
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States
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15
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Sharma L, Feng J, Britto CJ, Dela Cruz CS. Mechanisms of Epithelial Immunity Evasion by Respiratory Bacterial Pathogens. Front Immunol 2020; 11:91. [PMID: 32117248 PMCID: PMC7027138 DOI: 10.3389/fimmu.2020.00091] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/14/2020] [Indexed: 01/14/2023] Open
Abstract
Bacterial lung infections are major healthcare challenges killing millions of people worldwide and resulting in a huge economic burden. Both basic and clinical research have elucidated host mechanisms that contribute to the bacterial clearance where an indispensable role of immune cells has been established. However, the role of respiratory epithelial cells in bacterial clearance has garnered limited attention due to their weak inflammatory or phagocytic ability compared to immune cells such as macrophages and neutrophils. These studies often underappreciate the fact that epithelial cells are the most abundant cells in the lung, not only serving as building blocks but also providing immune protection throughout the lung. Epithelial cells function either independently to eradicate the pathogen or communicate with immune cells to orchestrate pathogen clearance. The epithelial cells have multiple mechanisms that include mucus production, antimicrobial peptide production, muco-ciliary clearance, and phagocytosis, all of which contribute to their direct antibacterial function. Secretion of cytokines to recruit immune cells and potentiate their antimicrobial activities is a pathway by which the epithelium contributes to bacterial clearance. Successful pathogens outsmart epithelial resistance and find a way to replicate in sufficient numbers to establish infections in the airway or lung epithelial surfaces. In this mini-review, we discuss evidences that establish important roles for epithelial host defense against invading respiratory bacterial pathogens and demonstrate how pathogens outsmart these epithelial immune mechanisms to successfully establish infection. Finally, we discuss briefly how to boost epithelial immunity to improve outcomes in bacterial lung infections.
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Affiliation(s)
- Lokesh Sharma
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Jingjing Feng
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States.,Department of Respiratory Medicine, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Clemente J Britto
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Charles S Dela Cruz
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, CT, United States
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16
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Morrison CB, Markovetz MR, Ehre C. Mucus, mucins, and cystic fibrosis. Pediatr Pulmonol 2019; 54 Suppl 3:S84-S96. [PMID: 31715083 PMCID: PMC6853602 DOI: 10.1002/ppul.24530] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/06/2019] [Indexed: 02/06/2023]
Abstract
Cystic fibrosis (CF) is both the most common and most lethal genetic disease in the Caucasian population. CF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene and is characterized by the accumulation of thick, adherent mucus plaques in multiple organs, of which the lungs, gastrointestinal tract and pancreatic ducts are the most commonly affected. A similar pathogenesis cascade is observed in all of these organs: loss of CFTR function leads to altered ion transport, consisting of decreased chloride and bicarbonate secretion via the CFTR channel and increased sodium absorption via epithelial sodium channel upregulation. Mucosa exposed to changes in ionic concentrations sustain severe pathophysiological consequences. Altered mucus biophysical properties and weakened innate defense mechanisms ensue, furthering the progression of the disease. Mucins, the high-molecular-weight glycoproteins responsible for the viscoelastic properties of the mucus, play a key role in the disease but the actual mechanism of mucus accumulation is still undetermined. Multiple hypotheses regarding the impact of CFTR malfunction on mucus have been proposed and are reviewed here. (a) Dehydration increases mucin monomer entanglement, (b) defective Ca2+ chelation compromises mucin expansion, (c) ionic changes alter mucin interactions, and (d) reactive oxygen species increase mucin crosslinking. Although one biochemical change may dominate, it is likely that all of these mechanisms play some role in the progression of CF disease. This article discusses recent findings on the initial cause(s) of aberrant mucus properties in CF and examines therapeutic approaches aimed at correcting mucus properties.
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Affiliation(s)
- Cameron Bradley Morrison
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Matthew Raymond Markovetz
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Camille Ehre
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Division of Pediatric Pulmonology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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17
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Kao SS, Ramezanpour M, Bassiouni A, Wormald P, Psaltis AJ, Vreugde S. The effect of neutrophil serine proteases on human nasal epithelial cell barrier function. Int Forum Allergy Rhinol 2019; 9:1220-1226. [DOI: 10.1002/alr.22401] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/01/2019] [Accepted: 07/17/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Stephen Shih‐Teng Kao
- Department of Surgery–Otorhinolaryngology, Head and Neck SurgeryThe Queen Elizabeth Hospital, and the University of Adelaide Adelaide SA Australia
| | - Mahnaz Ramezanpour
- Department of Surgery–Otorhinolaryngology, Head and Neck SurgeryThe Queen Elizabeth Hospital, and the University of Adelaide Adelaide SA Australia
| | - Ahmed Bassiouni
- Department of Surgery–Otorhinolaryngology, Head and Neck SurgeryThe Queen Elizabeth Hospital, and the University of Adelaide Adelaide SA Australia
| | - Peter‐John Wormald
- Department of Surgery–Otorhinolaryngology, Head and Neck SurgeryThe Queen Elizabeth Hospital, and the University of Adelaide Adelaide SA Australia
| | - Alkis James Psaltis
- Department of Surgery–Otorhinolaryngology, Head and Neck SurgeryThe Queen Elizabeth Hospital, and the University of Adelaide Adelaide SA Australia
| | - Sarah Vreugde
- Department of Surgery–Otorhinolaryngology, Head and Neck SurgeryThe Queen Elizabeth Hospital, and the University of Adelaide Adelaide SA Australia
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18
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Moore PJ, Sesma J, Alexis NE, Tarran R. Tobacco exposure inhibits SPLUNC1-dependent antimicrobial activity. Respir Res 2019; 20:94. [PMID: 31113421 PMCID: PMC6530064 DOI: 10.1186/s12931-019-1066-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 05/06/2019] [Indexed: 11/24/2022] Open
Abstract
Background Tobacco smoke exposure impairs the lung’s innate immune response, leading to an increased risk of chronic infections. SPLUNC1 is a secreted, multifunctional innate defense protein that has antimicrobial activity against Gram negative organisms. We hypothesize that tobacco smoke-induced SPLUNC1 dysfunction contributes to the observed defect in innate immunity in tobacco smokers and that this dysfunction can be used as a potential biomarker of harm. Methods We collected sputum from never-smokers and otherwise healthy smokers. We performed Western blotting to determine SPLUNC1 levels and determined antimicrobial activity against nontypeable Haemophilus influenzae. An in vitro exposure model was utilized to measure the effect of tobacco exposure on human bronchial epithelial culture (HBEC) antimicrobial activity against H. influenzae. The direct effects of cigarette and little cigar smoke exposure on SPLUNC1 function was determined using 24 h growth measurements and LPS binding assays. Results H. influenzae growth in cigarette smoker’s sputum was significantly greater compared to never-smokers sputum over 24 h. HBEC supernatants and lysates contained significantly higher numbers of H. influenzae following chronic cigarette and little cigar smoke exposure compared to air-exposed controls. Furthermore, SPLUNC1’s antimicrobial activity and LPS-binding capability against both H. influenzae and P. aeruginosa was attenuated following cigarette and little cigar exposure. Conclusions These data suggest that cigarette and little cigar exposure impairs SPLUNC1’s antimicrobial ability and that this inhibition may serve as a novel biomarker of harm that can be used to assess the toxicity of commercial tobacco products.
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Affiliation(s)
- Patrick J Moore
- Marsico Lung Institute, University of North Carolina at Chapel Hill, 7118A Marsico Hall, 125 Mason Farm Road, Chapel Hill, NC, 27599, USA.
| | - Juliana Sesma
- CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Neil E Alexis
- Center for Environmental Medicine, Asthma and Lung Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Robert Tarran
- Marsico Lung Institute, University of North Carolina at Chapel Hill, 7118A Marsico Hall, 125 Mason Farm Road, Chapel Hill, NC, 27599, USA.,Department of Cell Biology & Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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19
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Webster MJ, Reidel B, Tan CD, Ghosh A, Alexis NE, Donaldson SH, Kesimer M, Ribeiro CMP, Tarran R. SPLUNC1 degradation by the cystic fibrosis mucosal environment drives airway surface liquid dehydration. Eur Respir J 2018; 52:13993003.00668-2018. [PMID: 30190268 DOI: 10.1183/13993003.00668-2018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 08/06/2018] [Indexed: 02/07/2023]
Abstract
The multi-organ disease cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane regulator gene (CFTR) that lead to diminished transepithelial anion transport. CF lungs are characterised by airway surface liquid (ASL) dehydration, chronic infection/inflammation and neutrophilia. Dysfunctional CFTR may upregulate the epithelial Na+ channel (ENaC), further exacerbating dehydration. We previously demonstrated that short palate lung and nasal epithelial clone 1 (SPLUNC1) negatively regulates ENaC in normal airway epithelia.Here, we used pulmonary tissue samples, sputum and human bronchial epithelial cells (HBECs) to determine whether SPLUNC1 could regulate ENaC in a CF-like environment.We found reduced endogenous SPLUNC1 in CF secretions, and rapid degradation of recombinant SPLUNC1 (rSPLUNC1) by CF secretions. Normal sputum, containing SPLUNC1 and SPLUNC1-derived peptides, inhibited ENaC in both normal and CF HBECs. Conversely, CF sputum activated ENaC, and rSPLUNC1 could not reverse this phenomenon. Additionally, we observed upregulation of ENaC protein levels in human CF bronchi. Unlike SPLUNC1, the novel SPLUNC1-derived peptide SPX-101 resisted protease degradation, bound apically to HBECs, inhibited ENaC and prevented ASL dehydration following extended pre-incubation with CF sputum.Our data indicate that CF mucosal secretions drive ASL hyperabsorption and that protease-resistant peptides, e.g. SPX-101, can reverse this effect to rehydrate CF ASL.
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Affiliation(s)
- Megan J Webster
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA
| | - Boris Reidel
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA
| | - Chong D Tan
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA
| | - Arunava Ghosh
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA
| | - Neil E Alexis
- Center for Asthma and Lung Biology, The University of North Carolina, Chapel Hill, NC, USA
| | - Scott H Donaldson
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA.,Division of Pulmonary and Critical Care Medicine, The University of North Carolina, Chapel Hill, NC, USA
| | - Mehmet Kesimer
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA
| | - Carla M P Ribeiro
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA.,Dept of Cell Biology and Physiology, The University of North Carolina, Chapel Hill, NC, USA
| | - Robert Tarran
- Marsico Lung Institute, The University of North Carolina, Chapel Hill, NC, USA .,Dept of Cell Biology and Physiology, The University of North Carolina, Chapel Hill, NC, USA
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20
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Webster MJ, Tarran R. Slippery When Wet: Airway Surface Liquid Homeostasis and Mucus Hydration. CURRENT TOPICS IN MEMBRANES 2018; 81:293-335. [PMID: 30243435 DOI: 10.1016/bs.ctm.2018.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The ability to regulate cell volume is crucial for normal physiology; equally the regulation of extracellular fluid homeostasis is of great importance. Alteration of normal extracellular fluid homeostasis contributes to the development of several diseases including cystic fibrosis. With regard to the airway surface liquid (ASL), which lies apically on top of airway epithelia, ion content, pH, mucin and protein abundance must be tightly regulated. Furthermore, airway epithelia must be able to switch from an absorptive to a secretory state as required. A heterogeneous population of airway epithelial cells regulate ASL solute and solvent composition, and directly secrete large mucin molecules, antimicrobials, proteases and soluble mediators into the airway lumen. This review focuses on how epithelial ion transport influences ASL hydration and ASL pH, with a specific focus on the roles of anion and cation channels and exchangers. The role of ions and pH in mucin expansion is also addressed. With regard to fluid volume regulation, we discuss the roles of nucleotides, adenosine and the short palate lung and nasal epithelial clone 1 (SPLUNC1) as soluble ASL mediators. Together, these mechanisms directly influence ciliary beating and in turn mucociliary clearance to maintain sterility and to detoxify the airways. Whilst all of these components are regulated in normal airways, defective ion transport and/or mucin secretion proves detrimental to lung homeostasis as such we address how defective ion and fluid transport, and a loss of homeostatic mechanisms, contributes to the development of pathophysiologies associated with cystic fibrosis.
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Affiliation(s)
- Megan J Webster
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Robert Tarran
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Cell Biology & Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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21
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The Role of BPIFA1 in Upper Airway Microbial Infections and Correlated Diseases. BIOMED RESEARCH INTERNATIONAL 2018; 2018:2021890. [PMID: 30255091 PMCID: PMC6140130 DOI: 10.1155/2018/2021890] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 07/04/2018] [Accepted: 08/07/2018] [Indexed: 12/16/2022]
Abstract
The mucosa is part of the first line of immune defense against pathogen exposure in humans and prevents viral and bacterial infection of the soft palate, lungs, uvula, and nasal cavity that comprise the ear-nose-throat (ENT) region. Bactericidal/permeability-increasing fold containing family A, member 1 (BPIFA1) is a secretory protein found in human upper aerodigestive tract mucosa. This innate material is secreted in mucosal fluid or found in submucosal tissue in the human soft palate, lung, uvula, and nasal cavity. BPIFA1 is a critical component of the innate immune response that prevents upper airway diseases. This review will provide a brief introduction of the roles of BPIFA1 in the upper airway (with a focus on the nasal cavity, sinus, and middle ear), specifically its history, identification, distribution in various human tissues, function, and diagnostic value in various upper airway infectious diseases.
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22
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Moore PJ, Tarran R. The epithelial sodium channel (ENaC) as a therapeutic target for cystic fibrosis lung disease. Expert Opin Ther Targets 2018; 22:687-701. [PMID: 30028216 DOI: 10.1080/14728222.2018.1501361] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Cystic fibrosis is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that codes for the CFTR anion channel. In the absence of functional CFTR, the epithelial Na+ channel is also dysregulated. Airway surface liquid (ASL) hydration is maintained by a balance between epithelial sodium channel (ENaC)-led Na+ absorption and CFTR-dependent anion secretion. This finely tuned homeostatic mechanism is required to maintain sufficient airway hydration to permit the efficient mucus clearance necessary for a sterile lung environment. In CF airways, the lack of CFTR and increased ENaC activity lead to ASL/mucus dehydration that causes mucus obstruction, neutrophilic infiltration, and chronic bacterial infection. Rehydration of ASL/mucus in CF airways can be achieved by inhibiting Na+ absorption with pharmacological inhibitors of ENaC. Areas covered: In this review, we discuss ENaC structure and function and its role in CF lung disease and focus on ENaC inhibition as a potential therapeutic target to rehydrate CF mucus. We also discuss the failure of the first generation of pharmacological inhibitors of ENaC and recent alternate strategies to attenuate ENaC activity in the CF lung. Expert opinion: ENaC is an attractive therapeutic target to rehydrate CF ASL that may serve as a monotherapy or function in parallel with other treatments. Given the increased number of strategies being employed to inhibit ENaC, this is an exciting and optimistic time to be in this field.
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Affiliation(s)
- Patrick J Moore
- a Marsico Lung Institute , University of North Carolina , Chapel Hill , NC , USA
| | - Robert Tarran
- a Marsico Lung Institute , University of North Carolina , Chapel Hill , NC , USA.,b Department of Cell Biology & Physiology , University of North Carolina , Chapel Hill , NC , USA
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23
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Moore PJ, Reidel B, Ghosh A, Sesma J, Kesimer M, Tarran R. Cigarette smoke modifies and inactivates SPLUNC1, leading to airway dehydration. FASEB J 2018; 32:fj201800345R. [PMID: 29890087 PMCID: PMC6219833 DOI: 10.1096/fj.201800345r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 05/21/2018] [Indexed: 01/14/2023]
Abstract
Chronic obstructive pulmonary disease (COPD) is a growing cause of morbidity and mortality worldwide. Cigarette smoke (CS) exposure, a major cause of COPD, dysregulates airway epithelial ion transport and diminishes airway surface liquid (ASL) volume. Short palate lung and nasal epithelial clone 1 (SPLUNC1) is secreted into the airway lumen where it maintains airway hydration via interactions with the epithelial Na+ channel (ENaC). Although ASL hydration is dysregulated in CS-exposed/COPD airways, effects of CS on SPLUNC1 have not been elucidated. We hypothesized that CS alters SPLUNC1 activity, therefore contributing to ASL dehydration. CS exposure caused irreversible SPLUNC1 aggregation and prevented SPLUNC1 from internalizing ENaC and maintaining ASL hydration. Proteomic analysis revealed αβ-unsaturated aldehyde modifications to SPLUNC1's cysteine residues. Removal of these cysteines prevented SPLUNC1 from regulating ENaC/ASL volume. In contrast, SPX-101, a peptide mimetic of natural SPLUNC1, that internalizes ENaC, but does not contain cysteines was unaffected by CS. SPX-101 increased ASL hydration and attenuated ENaC activity in airway cultures after CS exposure and prolonged survival in a chronic airway disease model. These findings suggest that the CS-induced defects in SPLUNC1 can be circumvented, thus making SPX-101 a novel candidate for the treatment of mucus dehydration in COPD. -Moore, P. J., Reidel, B., Ghosh, A., Sesma, J., Kesimer, M., Tarran, R. Cigarette smoke modifies and inactivates SPLUNC1, leading to airway dehydration.
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Affiliation(s)
- Patrick J. Moore
- Marsico Lung Institute, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Boris Reidel
- Marsico Lung Institute, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Arunava Ghosh
- Marsico Lung Institute, University of North Carolina at Chapel Hill, North Carolina, USA
| | | | - Mehmet Kesimer
- Marsico Lung Institute, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Robert Tarran
- Marsico Lung Institute, University of North Carolina at Chapel Hill, North Carolina, USA
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, North Carolina, USA
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24
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Little MS, Redinbo MR. Crystal structure of the mouse innate immunity factor bacterial permeability-increasing family member A1. Acta Crystallogr F Struct Biol Commun 2018; 74:268-276. [PMID: 29717993 PMCID: PMC5931138 DOI: 10.1107/s2053230x18004600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 03/20/2018] [Indexed: 01/14/2023] Open
Abstract
Bacterial permeability-increasing family member A1 (BPIFA1) is an innate immunity factor and one of the most abundantly secreted proteins in the upper airways. BPIFA1 is multifunctional, with antimicrobial, surfactant and lipopolysaccharide-binding activities, as well as established roles in lung hydration. Here, the 2.5 Å resolution crystal structure of BPIFA1 from Mus musculus (mBPIFA1) is presented and compared with those of human BPIFA1 (hBPIFA1) and structural homologs. Structural distinctions between mBPIFA1 and hBPIFA1 suggest potential differences in biological function, including the regulation of a key pulmonary ion channel.
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Affiliation(s)
- Michael S. Little
- Department of Chemistry, University of North Carolina, 4350 Genome Sciences Building, Chapel Hill, NC 27599-3290, USA
| | - Matthew R. Redinbo
- Department of Chemistry, University of North Carolina, 4350 Genome Sciences Building, Chapel Hill, NC 27599-3290, USA
- Department of Biochemistry and Biophysics, University of North Carolina, 4350 Genome Sciences Building, Chapel Hill, NC 27599-3290, USA
- Department of Microbiology and Immunology and the Integrated Program for Biological and Genome Science, University of North Carolina, 4350 Genome Sciences Building, Chapel Hill, NC 27599-3290, USA
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25
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De Smet EG, Seys LJM, Verhamme FM, Vanaudenaerde BM, Brusselle GG, Bingle CD, Bracke KR. Association of innate defense proteins BPIFA1 and BPIFB1 with disease severity in COPD. Int J Chron Obstruct Pulmon Dis 2017; 13:11-27. [PMID: 29296079 PMCID: PMC5741069 DOI: 10.2147/copd.s144136] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is characterized by an abnormal inflammatory response in the lungs caused by the inhalation of noxious particles and gases. The airway epithelium has a protective function against these harmful agents by maintaining a physical barrier and by secreting defensive proteins, such as bactericidal/permeability-increasing fold-containing (BPIF) proteins, BPIFA1 and BPIFB1. However, inconsistent data regarding BPIFA1 expression in smokers and COPD patients have been reported to date. Therefore, we investigated the expression of BPIFA1 and BPIFB1 in a large cohort of never-smokers and smokers with and without COPD, both on the messenger RNA (mRNA) level in lung tissue and on the protein level in airway epithelium. Furthermore, we examined the correlation between BPIFA1 and BPIFB1 levels, goblet cell hyperplasia, and lung function measurements. BPIFA1 and BPIFB1 mRNA expressions were significantly increased in stage III-IV COPD patients compared with stage II COPD patients and subjects without COPD. In addition, protein levels in COPD patients were significantly increased in comparison with subjects without COPD. BPIFA1 and BPIFB1 levels were inversely correlated with measurements of airflow limitation and positively correlated with goblet cell hyperplasia. In addition, by the use of immunofluorescence double staining, we demonstrated the expression of BPIFB1 in goblet cells. In conclusion, we show that BPIFA1 and BPIFB1 levels are elevated in COPD patients and correlate with disease severity.
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Affiliation(s)
- Elise G De Smet
- Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Leen JM Seys
- Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
- Laboratory of Immunoregulation and Mucosal Immunology, VIB-UGent Center for Inflammation Research, Ghent, Belgium
| | - Fien M Verhamme
- Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Bart M Vanaudenaerde
- Laboratory for Respiratory Diseases, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Guy G Brusselle
- Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Colin D Bingle
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The University of Sheffield, Sheffield, UK
| | - Ken R Bracke
- Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
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Terryah ST, Fellner RC, Ahmad S, Moore PJ, Reidel B, Sesma JI, Kim CS, Garland AL, Scott DW, Sabater JR, Carpenter J, Randell SH, Kesimer M, Abraham WM, Arendshorst WJ, Tarran R. Evaluation of a SPLUNC1-derived peptide for the treatment of cystic fibrosis lung disease. Am J Physiol Lung Cell Mol Physiol 2017; 314:L192-L205. [PMID: 28982737 DOI: 10.1152/ajplung.00546.2016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
In cystic fibrosis (CF) lungs, epithelial Na+ channel (ENaC) hyperactivity causes a reduction in airway surface liquid volume, leading to decreased mucocilliary clearance, chronic bacterial infection, and lung damage. Inhibition of ENaC is an attractive therapeutic option. However, ENaC antagonists have failed clinically because of off-target effects in the kidney. The S18 peptide is a naturally occurring short palate lung and nasal epithelial clone 1 (SPLUNC1)-derived ENaC antagonist that restores airway surface liquid height for up to 24 h in CF human bronchial epithelial cultures. However, its efficacy and safety in vivo are unknown. To interrogate the potential clinical efficacy of S18, we assessed its safety and efficacy using human airway cultures and animal models. S18-mucus interactions were tested using superresolution microscopy, quartz crystal microbalance with dissipation, and confocal microscopy. Human and murine airway cultures were used to measure airway surface liquid height. Off-target effects were assessed in conscious mice and anesthetized rats. Morbidity and mortality were assessed in the β-ENaC-transgenic (Tg) mouse model. Restoration of normal mucus clearance was measured in cystic fibrosis transmembrane conductance regulator inhibitor 172 [CFTR(inh)-172]-challenged sheep. We found that S18 does not interact with mucus and rapidly penetrated dehydrated CF mucus. Compared with amiloride, an early generation ENaC antagonist, S18 displayed a superior ability to slow airway surface liquid absorption, reverse CFTR(inh)-172-induced reduction of mucus transport, and reduce morbidity and mortality in the β-ENaC-Tg mouse, all without inducing any detectable signs of renal toxicity. These data suggest that S18 is the first naturally occurring ENaC antagonist to show improved preclinical efficacy in animal models of CF with no signs of renal toxicity.
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Affiliation(s)
- Shawn T Terryah
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Robert C Fellner
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Saira Ahmad
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Patrick J Moore
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Boris Reidel
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | | | - Christine S Kim
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Alaina L Garland
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | | | - Juan R Sabater
- Department of Research, Mount Sinai Medical Center , Miami Beach, Florida
| | - Jerome Carpenter
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Scott H Randell
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.,Cell Biology and Physiology, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Mehmet Kesimer
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - William M Abraham
- Department of Research, Mount Sinai Medical Center , Miami Beach, Florida
| | - William J Arendshorst
- Cell Biology and Physiology, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Robert Tarran
- Cystic Fibrosis Center/Marsico Lung Institute, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.,Cell Biology and Physiology, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
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Targets of Neutrophil Influx and Weaponry: Therapeutic Opportunities for Chronic Obstructive Airway Disease. J Immunol Res 2017; 2017:5273201. [PMID: 28596972 PMCID: PMC5449733 DOI: 10.1155/2017/5273201] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/23/2017] [Accepted: 03/30/2017] [Indexed: 12/31/2022] Open
Abstract
Neutrophils are important effector cells of antimicrobial immunity in an acute inflammatory response, with a primary role in the clearance of extracellular pathogens. However, in respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD), there is excessive infiltration and activation of neutrophils, subsequent production of reactive oxygen species, and release of serine proteases, matrix metalloproteinases, and myeloperoxidase—resulting in collateral damage as the cells infiltrate into the tissue. Increased neutrophil survival through dysregulated apoptosis facilitates continued release of neutrophil-derived mediators to perpetuate airway inflammation and tissue injury. Several target mechanisms have been investigated to address pathologic neutrophil biology and thereby provide a novel therapy for respiratory disease. These include neutrophil influx through inhibition of chemokine receptors CXCR2, CXCR1, and PI3Kγ signaling and neutrophil weaponry by protease inhibitors, targeting matrix metalloproteinases and neutrophil serine proteases. In addition, neutrophil function can be modulated using selective PI3Kδ inhibitors. This review highlights the latest advances in targeting neutrophils and their function, discusses the opportunities and risks of neutrophil inhibition, and explores how we might better develop future strategies to regulate neutrophil influx and function for respiratory diseases in dire need of novel effective therapies.
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28
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Jiang D, Berman R, Wu Q, Stevenson C, Chu HW. The Anti-inflammatory Effect of Alpha-1 Antitrypsin in Rhinovirus-infected Human Airway Epithelial Cells. ACTA ACUST UNITED AC 2016; 7. [PMID: 28191362 DOI: 10.4172/2155-9899.1000475] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Excessive airway inflammation is seen in chronic obstructive pulmonary disease (COPD) patients experiencing acute exacerbations, which are often associated with human rhinovirus (HRV) infection. Alpha-1 antitrypsin (A1AT) has anti-inflammatory function in endothelial cells and monocytes, but its anti-inflammatory effect has not been investigated in COPD airway epithelial cells. We determined A1AT's anti-inflammatory function in COPD airway epithelial cells and the underlying mechanisms such as the role of caspase-1. METHODS Brushed bronchial epithelial cells from COPD and normal subjects were cultured at air-liquid interface and treated with A1AT or bovine serum albumin (BSA, control) two hours prior to whole cigarette smoke (WCS) or air exposure, followed by HRV-16 infection. After 24 hours of viral infection, cell supernatants were collected for measuring IL-8, and cells were examined for caspase-1. The in vivo anti-inflammatory function of A1AT was determined by infecting mice intranasally with HRV-1B followed by aerosolized A1AT or BSA. RESULTS A1AT significantly reduced WCS and HRV-16-induced IL-8 production in normal and COPD airway epithelial cells. COPD cells are less sensitive to A1AT's anti-inflammatory effect than normal cells. A1AT exerted the anti-inflammatory function in part via reducing caspase-1 in normal cells, but not in COPD cells. In mice, A1AT significantly reduced HRV-1B induced lung neutrophilic inflammation. CONCLUSIONS A1AT exerts an anti-inflammatory effect in cigarette smoke-exposed and HRV-infected human airway epithelial cells, which may be related to its inhibitory effect on caspase-1 activity.
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Affiliation(s)
- Di Jiang
- Department of Medicine, National Jewish Health, Denver, CO, USA
| | - Reena Berman
- Department of Medicine, National Jewish Health, Denver, CO, USA
| | - Qun Wu
- Department of Medicine, National Jewish Health, Denver, CO, USA
| | | | - Hong Wei Chu
- Department of Medicine, National Jewish Health, Denver, CO, USA; Department of Immunology and Microbiology, University of Colorado Denver School of Medicine, Aurora, CO, USA
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Elborn JS, Horsley A, MacGregor G, Bilton D, Grosswald R, Ahuja S, Springman EB. Phase I Studies of Acebilustat: Biomarker Response and Safety in Patients with Cystic Fibrosis. Clin Transl Sci 2016; 10:28-34. [PMID: 27806191 PMCID: PMC5351012 DOI: 10.1111/cts.12428] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 12/21/2022] Open
Abstract
There is a significant unmet need for safe and effective anti‐inflammatory treatment for cystic fibrosis. The aim of this study was to evaluate the safety of acebilustat, a leukotriene A4 hydrolase inhibitor, and its effect on inflammation biomarkers in patients with cystic fibrosis. Seventeen patients with mild to moderate cystic fibrosis were enrolled and randomized into groups receiving placebo or doses of 50 mg or 100 mg acebilustat administered orally, once daily for 15 days. Sputum neutrophil counts were reduced by 65% over baseline values in patients treated with 100 mg acebilustat. A modestly significant 58% reduction vs. placebo in sputum elastase was observed with acebilustat treatment. Favorable trends were observed for reduction of serum C‐reactive protein and sputum neutrophil DNA in acebilustat‐treated patients. No changes in pulmonary function were observed. Acebilustat was safe and well tolerated. The results of this study support further clinical development of acebilustat for treatment of cystic fibrosis.
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Affiliation(s)
- J S Elborn
- Centre for Infection and Immunity, Dentistry, and Biomedical Sciences, Queens University School of Medicine, Belfast, UK
| | - A Horsley
- Centre for Respiratory Medicine and Allergy, Institute of Inflammation and Repair, University of Manchester, Manchester, UK
| | - G MacGregor
- West of Scotland CF Centre, Gartnavel General Hospital, Glasgow, UK
| | - D Bilton
- Department of Respiratory Medicine, Royal Brompton Hospital, London, UK
| | | | - S Ahuja
- Celtaxsys, Inc, Atlanta, Georgia, USA
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30
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Short Palate, Lung, and Nasal Epithelial Clone 1 Has Antimicrobial and Antibiofilm Activities against the Burkholderia cepacia Complex. Antimicrob Agents Chemother 2016; 60:6003-12. [PMID: 27458217 DOI: 10.1128/aac.00975-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/17/2016] [Indexed: 02/07/2023] Open
Abstract
The opportunistic bacteria of the Burkholderia cepacia complex (Bcc) are extremely pathogenic to cystic fibrosis (CF) patients, and acquisition of Bcc bacteria is associated with a significant increase in mortality. Treatment of Bcc infections is difficult because the bacteria are multidrug resistant and able to survive in biofilms. Short palate, lung, and nasal epithelial clone 1 (SPLUNC1) is an innate defense protein that is secreted by the upper airways and pharynx. While SPLUNC1 is known to have antimicrobial functions, its effects on Bcc strains are unclear. We therefore tested the hypothesis that SPLUNC1 is able to impair Bcc growth and biofilm formation. We found that SPLUNC1 exerted bacteriostatic effects against several Bcc clinical isolates, including B. cenocepacia strain J2315 (50% inhibitory concentration [IC50] = 0.28 μM), and reduced biofilm formation and attachment (IC50 = 0.11 μM). We then determined which domains of SPLUNC1 are responsible for its antimicrobial activity. Deletions of SPLUNC1's N terminus and α6 helix did not affect its function. However, deletion of the α4 helix attenuated antimicrobial activity, while the corresponding α4 peptide displayed antimicrobial activity. Chronic neutrophilia is a hallmark of CF lung disease, and neutrophil elastase (NE) cleaves SPLUNC1. However, we found that the ability of SPLUNC1 to disrupt biofilm formation was significantly potentiated by NE pretreatment. While the impact of CF on SPLUNC1-Bcc interactions is not currently known, our data suggest that understanding this interaction may have important implications for CF lung disease.
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31
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Higham A, Rattray NJW, Dewhurst JA, Trivedi DK, Fowler SJ, Goodacre R, Singh D. Electronic cigarette exposure triggers neutrophil inflammatory responses. Respir Res 2016; 17:56. [PMID: 27184092 PMCID: PMC4869345 DOI: 10.1186/s12931-016-0368-x] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 02/27/2016] [Indexed: 01/02/2023] Open
Abstract
Background The use of electronic cigarettes (e-cigs) is increasing and there is widespread perception that e-cigs are safe. E-cigs contain harmful chemicals; more research is needed to evaluate the safety of e-cig use. Our aim was to investigate the effects of e-cigs on the inflammatory response of human neutrophils. Methods Neutrophils were exposed to e-cig vapour extract (ECVE) and the expression of CD11b and CD66b was measured by flow cytometry and MMP-9 and CXCL8 by ELISA. We also measured the activity of neutrophil elastase (NE) and MMP-9, along with the activation of inflammatory signalling pathways. Finally we analysed the biochemical composition of ECVE by ultra-high performance liquid chromatography mass spectrometry. Results ECVE caused an increase in the expression of CD11b and CD66b, and increased the release of MMP-9 and CXCL8. Furthermore, there was an increase in NE and MMP-9 activity and an increase in p38 MAPK activation. We also identified several harmful chemicals in ECVE, including known carcinogens. Conclusions ECVE causes a pro-inflammatory response from human neutrophils. This raises concerns over the safety of e-cig use. Electronic supplementary material The online version of this article (doi:10.1186/s12931-016-0368-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andrew Higham
- Manchester Academic Health and Science Centre, University Hospital of South Manchester Foundation Trust, Centre for Respiratory and Allergy Medicine, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK.
| | - Nicholas J W Rattray
- Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, UK
| | - Jennifer A Dewhurst
- Manchester Academic Health and Science Centre, University Hospital of South Manchester Foundation Trust, Centre for Respiratory and Allergy Medicine, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
| | - Drupad K Trivedi
- Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, UK
| | - Stephen J Fowler
- Manchester Academic Health and Science Centre, University Hospital of South Manchester Foundation Trust, Centre for Respiratory and Allergy Medicine, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
| | - Royston Goodacre
- Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, UK
| | - Dave Singh
- Manchester Academic Health and Science Centre, University Hospital of South Manchester Foundation Trust, Centre for Respiratory and Allergy Medicine, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
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32
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Lecaille F, Lalmanach G, Andrault PM. Antimicrobial proteins and peptides in human lung diseases: A friend and foe partnership with host proteases. Biochimie 2015; 122:151-68. [PMID: 26341472 DOI: 10.1016/j.biochi.2015.08.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 08/31/2015] [Indexed: 12/20/2022]
Abstract
Lung antimicrobial proteins and peptides (AMPs) are major sentinels of innate immunity by preventing microbial colonization and infection. Nevertheless bactericidal activity of AMPs against Gram-positive and Gram-negative bacteria is compromised in patients with chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF) and asthma. Evidence is accumulating that expression of harmful human serine proteases, matrix metalloproteases and cysteine cathepsins is markedely increased in these chronic lung diseases. The local imbalance between proteases and protease inhibitors compromises lung tissue integrity and function, by not only degrading extracellular matrix components, but also non-matrix proteins. Despite the fact that AMPs are somewhat resistant to proteolytic degradation, some human proteases cleave them efficiently and impair their antimicrobial potency. By contrast, certain AMPs may be effective as antiproteases. Host proteases participate in concert with bacterial proteases in the degradation of key innate immunity peptides/proteins and thus may play immunomodulatory activities during chronic lung diseases. In this context, the present review highlights the current knowledge and recent discoveries on the ability of host enzymes to interact with AMPs, providing a better understanding of the role of human proteases in innate host defense.
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Affiliation(s)
- Fabien Lecaille
- INSERM, UMR 1100, Pathologies Respiratoires: Protéolyse et Aérosolthérapie, Centre d'Etude des Pathologies Respiratoires, Equipe 2: « Mécanismes Protéolytiques dans l'Inflammation », Université François Rabelais, F-37032 Tours cedex, France.
| | - Gilles Lalmanach
- INSERM, UMR 1100, Pathologies Respiratoires: Protéolyse et Aérosolthérapie, Centre d'Etude des Pathologies Respiratoires, Equipe 2: « Mécanismes Protéolytiques dans l'Inflammation », Université François Rabelais, F-37032 Tours cedex, France
| | - Pierre-Marie Andrault
- INSERM, UMR 1100, Pathologies Respiratoires: Protéolyse et Aérosolthérapie, Centre d'Etude des Pathologies Respiratoires, Equipe 2: « Mécanismes Protéolytiques dans l'Inflammation », Université François Rabelais, F-37032 Tours cedex, France
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von Nussbaum F, Li VMJ. Neutrophil elastase inhibitors for the treatment of (cardio)pulmonary diseases: Into clinical testing with pre-adaptive pharmacophores. Bioorg Med Chem Lett 2015; 25:4370-81. [PMID: 26358162 DOI: 10.1016/j.bmcl.2015.08.049] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 08/14/2015] [Accepted: 08/20/2015] [Indexed: 02/04/2023]
Abstract
Alpha-1 antitrypsin deficiency is linked with an increased risk of suffering from lung emphysema. This discovery from the 1960s led to the development of the protease-antiprotease (im)balance hypothesis: Overshooting protease concentrations, especially high levels of elastase were deemed to have an destructive effect on lung tissue. Consequently, it was postulated that efficient elastase inhibitors could alleviate the situation in patients. However, despite intensive drug discovery efforts, even five decades later, no neutrophil elastase inhibitors are available for a disease-modifying treatment of (cardio)pulmonary diseases such as chronic obstructive pulmonary disease. Here, we critically review the attempts to develop effective human neutrophil elastase inhibitors while strongly focussing on recent developments. On purpose and with perspective distortion we focus on recent developments. One aim of this review is to classify the known HNE inhibitors into several generations, according to their binding modes. In general, there seem to be three major challenges in the development of suitable elastase inhibitors: (1) assuring sufficient potency, (2) securing selectivity, and (3) achieving metabolic stability especially under pathophysiological conditions. Impressive achievements have been made since 2001 with the identification of potent nonreactive, reversible small molecule inhibitors. The most modern inhibitors bind HNE via an induced fit with a frozen bioactive conformation that leads to a significant boost in potency, selectivity, and stability ('pre-adaptive pharmacophores'). These 5th generation inhibitors might succeed in re-establishing the protease-antiprotease balance in patients for the first time.
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Affiliation(s)
| | - Volkhart M-J Li
- Bayer HealthCare AG, Lead Discovery Wuppertal, 42096 Wuppertal, Germany.
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Britto CJ, Cohn L. Bactericidal/Permeability-increasing protein fold-containing family member A1 in airway host protection and respiratory disease. Am J Respir Cell Mol Biol 2015; 52:525-34. [PMID: 25265466 DOI: 10.1165/rcmb.2014-0297rt] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Bactericidal/permeability-increasing protein fold-containing family member A1 (BPIFA1), formerly known as SPLUNC1, is one of the most abundant proteins in respiratory secretions and has been identified with increasing frequency in studies of pulmonary disease. Its expression is largely restricted to the respiratory tract, being highly concentrated in the upper airways and proximal trachea. BPIFA1 is highly responsive to airborne pathogens, allergens, and irritants. BPIFA1 actively participates in host protection through antimicrobial, surfactant, airway surface liquid regulation, and immunomodulatory properties. Its expression is modulated in multiple lung diseases, including cystic fibrosis, chronic obstructive pulmonary disease, respiratory malignancies, and idiopathic pulmonary fibrosis. However, the role of BPIFA1 in pulmonary pathogenesis remains to be elucidated. This review highlights the versatile properties of BPIFA1 in antimicrobial protection and its roles as a sensor of environmental exposure and regulator of immune cell function. A greater understanding of the contribution of BPIFA1 to disease pathogenesis and activity may clarify if BPIFA1 is a biomarker and potential drug target in pulmonary disease.
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Affiliation(s)
- Clemente J Britto
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut
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35
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Electronic cigarette liquid increases inflammation and virus infection in primary human airway epithelial cells. PLoS One 2014; 9:e108342. [PMID: 25244293 PMCID: PMC4171526 DOI: 10.1371/journal.pone.0108342] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 08/27/2014] [Indexed: 11/19/2022] Open
Abstract
Background/Objective The use of electronic cigarettes (e-cigarettes) is rapidly increasing in the United States, especially among young people since e-cigarettes have been perceived as a safer alternative to conventional tobacco cigarettes. However, the scientific evidence regarding the human health effects of e-cigarettes on the lung is extremely limited. The major goal of our current study is to determine if e-cigarette use alters human young subject airway epithelial functions such as inflammatory response and innate immune defense against respiratory viral (i.e., human rhinovirus, HRV) infection. Methodology/Main Results We examined the effects of e-cigarette liquid (e-liquid) on pro-inflammatory cytokine (e.g., IL-6) production, HRV infection and host defense molecules (e.g., short palate, lung, and nasal epithelium clone 1, SPLUNC1) in primary human airway epithelial cells from young healthy non-smokers. Additionally, we examined the role of SPLUNC1 in lung defense against HRV infection using a SPLUNC1 knockout mouse model. We found that nicotine-free e-liquid promoted IL-6 production and HRV infection. Addition of nicotine into e-liquid further amplified the effects of nicotine-free e-liquid. Moreover, SPLUNC1 deficiency in mice significantly increased lung HRV loads. E-liquid inhibited SPLUNC1 expression in primary human airway epithelial cells. These findings strongly suggest the deleterious health effects of e-cigarettes in the airways of young people. Our data will guide future studies to evaluate the impact of e-cigarettes on lung health in human populations, and help inform the public about potential health risks of e-cigarettes.
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Neutrophil elastase causes tissue damage that decreases host tolerance to lung infection with burkholderia species. PLoS Pathog 2014; 10:e1004327. [PMID: 25166912 PMCID: PMC4148436 DOI: 10.1371/journal.ppat.1004327] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 07/11/2014] [Indexed: 02/07/2023] Open
Abstract
Two distinct defense strategies can protect the host from infection: resistance is the ability to destroy the infectious agent, and tolerance is the ability to withstand infection by minimizing the negative impact it has on the host's health without directly affecting pathogen burden. Burkholderia pseudomallei is a Gram-negative bacterium that infects macrophages and causes melioidosis. We have recently shown that inflammasome-triggered pyroptosis and IL-18 are equally important for resistance to B. pseudomallei, whereas IL-1β is deleterious. Here we show that the detrimental role of IL-1β during infection with B. pseudomallei (and closely related B. thailandensis) is due to excessive recruitment of neutrophils to the lung and consequent tissue damage. Mice deficient in the potentially damaging enzyme neutrophil elastase were less susceptible than the wild type C57BL/6J mice to infection, although the bacterial burdens in organs and the extent of inflammation were comparable between C57BL/6J and elastase-deficient mice. In contrast, lung tissue damage and vascular leakage were drastically reduced in elastase-deficient mice compared to controls. Bradykinin levels were higher in C57BL/6 than in elastase-deficient mice; administration of a bradykinin antagonist protected mice from infection, suggesting that increased vascular permeability mediated by bradykinin is one of the mechanisms through which elastase decreases host tolerance to melioidosis. Collectively, these results demonstrate that absence of neutrophil elastase increases host tolerance, rather than resistance, to infection by minimizing host tissue damage.
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Tarran R, Redinbo MR. Mammalian short palate lung and nasal epithelial clone 1 (SPLUNC1) in pH-dependent airway hydration. Int J Biochem Cell Biol 2014; 52:130-5. [PMID: 24631954 PMCID: PMC4048990 DOI: 10.1016/j.biocel.2014.03.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 02/22/2014] [Accepted: 03/03/2014] [Indexed: 12/12/2022]
Abstract
The epithelia that line the conducting airways are the lung's first point of contact with inhaled pathogens and toxicants. As such, they are known to play an important role in the lung's innate defense system, which includes (i) the production of airway surface liquid (ASL) that helps cleanse the airways through the physical removal of pathogens and toxicants on the mucociliary escalator and (ii) the secretion of anti-microbial proteins into the ASL to kill inhaled pathogens. Interestingly, the recently crystallized short palate lung and nasal epithelial clone 1 (SPLUNC1) protein appears to be a multi-functional protein. That is, it not only acts as an anti-microbial agent, but also modulates ASL homeostasis by acting as an endogenous inhibitor of the epithelial Na(+) channel (ENaC). This review will focus on the latter function of SPLUNC1, and will discuss new structural and physiological data regarding SPLUNC1's failure to function as a regulator of ASL hydration in CF airways.
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Affiliation(s)
- Robert Tarran
- Cystic Fibrosis/Pulmonary Research and Treatment Center, Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC 27599, USA.
| | - Matthew R Redinbo
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599, USA.
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Irander K, Borres MP, Ghafouri B. The effects of physical exercise and smoking habits on the expression of SPLUNC1 in nasal lavage fluids from allergic rhinitis subjects. Int J Pediatr Otorhinolaryngol 2014; 78:618-22. [PMID: 24512783 DOI: 10.1016/j.ijporl.2014.01.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/11/2014] [Accepted: 01/14/2014] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Palate lung nasal epithelial clone (PLUNC) is a family of proteins, which are proposed to participate in the innate immune defense against infections in the upper aero-digestive tract. The aim of this study was to investigate the expression of SPLUNC1 in allergic rhinitis subjects with considerations taken to the mucosal function and smoking habits. METHODS The participants, recruited from a cohort followed from infancy, were re-examined at the age of 18 years regarding allergy development. Based on medical histories and skin prick tests the participants were classified into groups with persistent allergic rhinitis (n=18), intermittent allergic rhinitis (n = 8) and healthy controls (n = 13). Seven subjects (3, 2 and 2 in each group, respectively) reported smoking habits. The SPLUNC1 levels in nasal lavage fluids were analyzed by Western blot. Changes in the volume of the proper nasal cavity before and after physical exercise (Vol2(increase)) were analyzed by acoustic rhinometry. RESULTS Compared to the control group the SPLUNC1 level was significantly lower in the persistent allergy group (3.8 ± 3.4 OD vs. 1.3 ± 1.5 OD; p = 0.02), but not in the intermittent allergy group without current exposure to allergens (3.6 ± 4.7 OD). No differences were found in Vol2(increase) between any of the allergy groups and controls. In smokers Vol2(increase) was significantly reduced (p < 0.01) and the SPLUNC1 levels were lower compared to non-smokers. A significant correlation was found between SPLUNC1 and Vol2(increase) (p < 0.01; r = 0.53) in non-smokers. CONCLUSIONS Current allergen exposure has an impact on SPLUNC1 expression in nasal lavage fluid, why allergy ought to be considered in study populations where analyses of SPLUNC1 levels are included in the reports. The normal nasal decongestion after exercise was not affected by allergy in contrast to smoking habits. The correlation between SPLUNC1 levels and Vol2(increase) in non-smokers may indicate involvement of SPLUNC1in the regulation of the normal function of the nasal mucosa. Complementary studies are needed to confirm the smoke-related reduction of SPLUNC1 expression and to analyze the possible participation of SPLUNC1 in the nasal mucosa regulation.
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Affiliation(s)
- K Irander
- Allergy Center, ENT Section, University Hospital, Linköping, Sweden
| | - M P Borres
- Department of Women's and Children's Health, Uppsala University, Sweden; Thermo Fisher Scientific, Uppsala, Sweden
| | - B Ghafouri
- Department of Medical and Health Sciences, Division of Community Medicine Rehabilitation Medicine, Faculty of Health Sciences, Linköping University, and Pain and Rehabilitation Centre, County Council of Östergötland, Linköping, Sweden; Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, and Centre of Occupational and Environmental Medicine, County Council of Östergötland, Linköping, Sweden.
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Fornander L, Graff P, Wåhlén K, Ydreborg K, Flodin U, Leanderson P, Lindahl M, Ghafouri B. Airway symptoms and biological markers in nasal lavage fluid in subjects exposed to metalworking fluids. PLoS One 2013; 8:e83089. [PMID: 24391738 PMCID: PMC3877012 DOI: 10.1371/journal.pone.0083089] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 11/08/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUNDS Occurrence of airway irritation among industrial metal workers was investigated. The aims were to study the association between exposures from water-based metal working fluids (MWF) and the health outcome among the personnel, to assess potential effects on the proteome in nasal mucous membranes, and evaluate preventive actions. METHODS The prevalence of airway symptoms related to work were examined among 271 metalworkers exposed to MWF and 24 metal workers not exposed to MWF at the same factory. At the same time, air levels of potentially harmful substances (oil mist, morpholine, monoethanolamine, formaldehyde) generated from MWF was measured. Nasal lavage fluid was collected from 13 workers and 15 controls and protein profiles were determined by a proteomic approach. RESULTS Airway symptoms were reported in 39% of the workers exposed to MWF although the measured levels of MWF substances in the work place air were low. Highest prevalence was found among workers handling the MWF machines but also those working in the same hall were affected. Improvement of the ventilation to reduce MWF exposure lowered the prevalence of airway problems. Protein profiling showed significantly higher levels of S100-A9 and lower levels of SPLUNC1, cystatin SN, Ig J and β2-microglobulin among workers with airway symptoms. CONCLUSIONS This study confirms that upper airway symptoms among metal workers are a common problem and despite low levels of MWF-generated substances, effects on airway immune proteins are found. Further studies to clarify the role of specific MWF components in connection to airway inflammation and the identified biological markers are warranted.
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Affiliation(s)
- Louise Fornander
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Pål Graff
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Centre of Occupational and Environmental Medicine, County Council of Östergötland, Linköping, Sweden
| | - Karin Wåhlén
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Kjell Ydreborg
- Clinic of Otorhinolaryngology, County Hospital Ryhov, Jönköping, Sweden
| | - Ulf Flodin
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Centre of Occupational and Environmental Medicine, County Council of Östergötland, Linköping, Sweden
| | - Per Leanderson
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Centre of Occupational and Environmental Medicine, County Council of Östergötland, Linköping, Sweden
| | - Mats Lindahl
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Bijar Ghafouri
- Occupational and Environmental Medicine, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Centre of Occupational and Environmental Medicine, County Council of Östergötland, Linköping, Sweden
- Rehabilitation Medicine, Department of Medical and Health Sciences, Faculty of Health Sciences, Linköping University, Pain and Rehabilitation Centre, County Council of Östergötland, Linköping, Sweden
- * E-mail:
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Jiang D, Persinger R, Wu Q, Gross A, Chu HW. α1-Antitrypsin promotes SPLUNC1-mediated lung defense against Pseudomonas aeruginosa infection in mice. Respir Res 2013; 14:122. [PMID: 24209388 PMCID: PMC3829673 DOI: 10.1186/1465-9921-14-122] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Accepted: 10/31/2013] [Indexed: 01/10/2023] Open
Abstract
Background Pseudomonas aeruginosa (PA) infection is involved in various lung diseases such as cystic fibrosis and chronic obstructive pulmonary disease. However, treatment of PA infection is not very effective in part due to antibiotic resistance. α1-antitrypsin (A1AT) has been shown to reduce PA infection in humans and animals, but the underlying mechanisms remain unclear. The goal of our study is to test whether a novel endogenous host defense protein, short palate, lung, and nasal epithelium clone 1 (SPLUNC1), is involved in the therapeutic effect of A1AT during lung PA infection. Method SPLUNC1 knockout (KO) and littermate wild-type (WT) mice on the C57BL/6 background were intranasally infected with PA to determine the therapeutic effects of A1AT. A1AT was aerosolized to mice 2 hrs after the PA infection, and mice were sacrificed 24 hrs later. PA load and inflammation were quantified in the lung, and SPLUNC1 protein in bronchoalveolar lavage (BAL) fluid was examined by Western blot. Results In WT mice, PA infection significantly increased neutrophil elastase (NE) activity, but reduced SPLUNC1 protein in BAL fluid. Notably, PA-infected mice treated with A1AT versus bovine serum albumin (BSA) demonstrated higher levels of SPLUNC1 protein expression, which are accompanied by lower levels of NE activity, lung bacterial load, and pro-inflammatory cytokine production. To determine whether A1AT therapeutic effects are dependent on SPLUNC1, lung PA load in A1AT- or BSA-treated SPLUNC1 KO mice was examined. Unlike the WT mice, A1AT treatment in SPLUNC1 KO mice had no significant impact on lung PA load and pro-inflammatory cytokine production. Conclusion A1AT reduces lung bacterial infection in mice in part by preventing NE-mediated SPLUNC1 degradation.
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Affiliation(s)
| | | | | | | | - Hong Wei Chu
- Department of Medicine, National Jewish Health, Denver, CO, USA.
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