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Chaudhary S, Rai P, Joshi A, Yadav P, Sesham K, Kumar S, Mridha AR, Baitha U, Nag TC, Soni KD, Trikha A, Yadav SC. Ultracellular Imaging of Bronchoalveolar Lavage from Young COVID-19 Patients with Comorbidities Showed Greater SARS-COV-2 Infection but Lesser Ultrastructural Damage Than the Older Patients. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2022; 28:1-25. [PMID: 36065953 DOI: 10.1017/s1431927622012430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In this study, we examined the cellular infectivity and ultrastructural changes due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the various cells of bronchoalveolar fluid (BALF) from intubated patients of different age groups (≥60 years and <60 years) and with common comorbidities such as diabetes, liver and kidney diseases, and malignancies. BALF of 79 patients (38 cases >60 and 41 cases <60 years) were studied by light microscopy, immunofluorescence, scanning, and transmission electron microscopy to evaluate the ultrastructural changes in the ciliated epithelium, type II pneumocytes, macrophages, neutrophils, eosinophils, lymphocytes, and anucleated granulocytes. This study demonstrated relatively a greater infection and better preservation of subcellular structures in these cells from BALF of younger patients (<60 years compared with the older patients (≥60 years). The different cells of BALF from the patients without comorbidities showed higher viral load compared with the patients with comorbidities. Diabetic patients showed maximum ultrastructural damage in BALF cells in the comorbid group. This study highlights the comparative effect of SARS-CoV-2 infection on the different airway and inflammatory cells of BALF at the subcellular levels among older and younger patients and in patients with comorbid conditions.
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Affiliation(s)
- Shikha Chaudhary
- Electron Microscope Facility, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Preeti Rai
- Electron Microscope Facility, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Arti Joshi
- Electron Microscope Facility, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Pooja Yadav
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Kishore Sesham
- Electron Microscope Facility, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Shailendra Kumar
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Asit Ranjan Mridha
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Upendra Baitha
- Department of Medicine, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Tapas Chandra Nag
- Electron Microscope Facility, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Kapil Dev Soni
- Anaesthesia and Critical Care, JPN Apex Trauma Center, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Anjan Trikha
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
| | - Subhash Chandra Yadav
- Electron Microscope Facility, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi 110029, India
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Sempere J, Rossi SA, Chamorro-Herrero I, González-Camacho F, de Lucas MP, Rojas-Cabañeros JM, Taborda CP, Zaragoza Ó, Yuste J, Zambrano A. Minilungs from Human Embryonic Stem Cells to Study the Interaction of Streptococcus pneumoniae with the Respiratory Tract. Microbiol Spectr 2022; 10:e0045322. [PMID: 35695525 PMCID: PMC9241785 DOI: 10.1128/spectrum.00453-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 05/20/2022] [Indexed: 11/20/2022] Open
Abstract
The new generation of organoids derived from human pluripotent stem cells holds a promising strategy for modeling host-bacteria interaction studies. Organoids recapitulate the composition, diversity of cell types, and, to some extent, the functional features of the native organ. We generated lung bud organoids derived from human embryonic stem cells to study the interaction of Streptococcus pneumoniae (pneumococcus) with the alveolar epithelium. Invasive pneumococcal disease is an important health problem that may occur as a result of the spread of pneumococcus from the lower respiratory tract to sterile sites. We show here an efficient experimental approach to model the main events of the pneumococcal infection that occur in the human lung, exploring bacterial adherence to the epithelium and internalization and triggering an innate response that includes the interaction with surfactant and the expression of representative cytokines and chemokines. Thus, this model, based on human minilungs, can be used to study pneumococcal virulence factors and the pathogenesis of different serotypes, and it will allow therapeutic interventions in a reliable human context. IMPORTANCE Streptococcus pneumoniae is responsible for high morbidity and mortalities rates worldwide, affecting mainly children and adults older than 65 years. Pneumococcus is also the most common etiologic agent of bacterial pneumonia and nonepidemic meningitis, and it is a frequent cause of bacterial sepsis. Although the introduction of pneumococcal vaccines has decreased the burden of pneumococcal disease, the rise of antibiotic-resistant strains and nonvaccine types by serotype replacement is worrisome. To study the biology of pneumococcus and to establish a reliable human model for pneumococcal pathogenesis, we generated human minilungs from embryonic stem cells. The results show that these organoids can be used to model some events occurring during the interaction of pneumococcus with the lung, such as adherence, internalization, and the initial alveolar innate response. This model also represents a great alternative for studying virulence factors involved in pneumonia, drug screening, and other therapeutic interventions.
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Affiliation(s)
- Julio Sempere
- Biotechnology of Stem Cells and Organoids, Chronic Diseases Program, Instituto de Salud Carlos III, Madrid, Spain
- Spanish Pneumococcal Reference Laboratory, Centro Nacional de Microbiología, and CIBER of Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - Suélen Andreia Rossi
- Biotechnology of Stem Cells and Organoids, Chronic Diseases Program, Instituto de Salud Carlos III, Madrid, Spain
- Department of Microbiology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
- Mycology Reference Laboratory, Centro Nacional de Microbiología and CIBER of Infectious Diseases (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Irene Chamorro-Herrero
- Biotechnology of Stem Cells and Organoids, Chronic Diseases Program, Instituto de Salud Carlos III, Madrid, Spain
| | - Fernando González-Camacho
- Spanish Pneumococcal Reference Laboratory, Centro Nacional de Microbiología, and CIBER of Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - María Pilar de Lucas
- Cellular Biology Unit, Chronic Diseases Program and CIBER of Cancer (CIBERONC), Instituto de Salud Carlos III, Madrid, Spain
| | - José María Rojas-Cabañeros
- Cellular Biology Unit, Chronic Diseases Program and CIBER of Cancer (CIBERONC), Instituto de Salud Carlos III, Madrid, Spain
| | - Carlos Pelleschi Taborda
- Department of Microbiology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Óscar Zaragoza
- Mycology Reference Laboratory, Centro Nacional de Microbiología and CIBER of Infectious Diseases (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - José Yuste
- Spanish Pneumococcal Reference Laboratory, Centro Nacional de Microbiología, and CIBER of Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - Alberto Zambrano
- Biotechnology of Stem Cells and Organoids, Chronic Diseases Program, Instituto de Salud Carlos III, Madrid, Spain
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3
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Keskinidou C, Vassiliou AG, Dimopoulou I, Kotanidou A, Orfanos SE. Mechanistic Understanding of Lung Inflammation: Recent Advances and Emerging Techniques. J Inflamm Res 2022; 15:3501-3546. [PMID: 35734098 PMCID: PMC9207257 DOI: 10.2147/jir.s282695] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 05/04/2022] [Indexed: 12/12/2022] Open
Abstract
Acute respiratory distress syndrome (ARDS) is a life-threatening lung injury characterized by an acute inflammatory response in the lung parenchyma. Hence, it is considered as the most appropriate clinical syndrome to study pathogenic mechanisms of lung inflammation. ARDS is associated with increased morbidity and mortality in the intensive care unit (ICU), while no effective pharmacological treatment exists. It is very important therefore to fully characterize the underlying pathobiology and the related mechanisms, in order to develop novel therapeutic approaches. In vivo and in vitro models are important pre-clinical tools in biological and medical research in the mechanistic and pathological understanding of the majority of diseases. In this review, we will present data from selected experimental models of lung injury/acute lung inflammation, which have been based on clinical disorders that can lead to the development of ARDS and related inflammatory lung processes in humans, including ventilation-induced lung injury (VILI), sepsis, ischemia/reperfusion, smoke, acid aspiration, radiation, transfusion-related acute lung injury (TRALI), influenza, Streptococcus (S.) pneumoniae and coronaviruses infection. Data from the corresponding clinical conditions will also be presented. The mechanisms related to lung inflammation that will be covered are oxidative stress, neutrophil extracellular traps, mitogen-activated protein kinase (MAPK) pathways, surfactant, and water and ion channels. Finally, we will present a brief overview of emerging techniques in the field of omics research that have been applied to ARDS research, encompassing genomics, transcriptomics, proteomics, and metabolomics, which may recognize factors to help stratify ICU patients at risk, predict their prognosis, and possibly, serve as more specific therapeutic targets.
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Affiliation(s)
- Chrysi Keskinidou
- First Department of Critical Care Medicine and Pulmonary Services, School of Medicine, National and Kapodistrian University of Athens, "Evangelismos" Hospital, Athens, Greece
| | - Alice G Vassiliou
- First Department of Critical Care Medicine and Pulmonary Services, School of Medicine, National and Kapodistrian University of Athens, "Evangelismos" Hospital, Athens, Greece
| | - Ioanna Dimopoulou
- First Department of Critical Care Medicine and Pulmonary Services, School of Medicine, National and Kapodistrian University of Athens, "Evangelismos" Hospital, Athens, Greece
| | - Anastasia Kotanidou
- First Department of Critical Care Medicine and Pulmonary Services, School of Medicine, National and Kapodistrian University of Athens, "Evangelismos" Hospital, Athens, Greece
| | - Stylianos E Orfanos
- First Department of Critical Care Medicine and Pulmonary Services, School of Medicine, National and Kapodistrian University of Athens, "Evangelismos" Hospital, Athens, Greece
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4
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Kosyreva A, Dzhalilova D, Lokhonina A, Vishnyakova P, Fatkhudinov T. The Role of Macrophages in the Pathogenesis of SARS-CoV-2-Associated Acute Respiratory Distress Syndrome. Front Immunol 2021; 12:682871. [PMID: 34040616 PMCID: PMC8141811 DOI: 10.3389/fimmu.2021.682871] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 04/22/2021] [Indexed: 12/11/2022] Open
Abstract
Macrophages are cells that mediate both innate and adaptive immunity reactions, playing a major role in both physiological and pathological processes. Systemic SARS-CoV-2-associated complications include acute respiratory distress syndrome (ARDS), disseminated intravascular coagulation syndrome, edema, and pneumonia. These are predominantly effects of massive macrophage activation that collectively can be defined as macrophage activation syndrome. In this review we focus on the role of macrophages in COVID-19, as pathogenesis of the new coronavirus infection, especially in cases complicated by ARDS, largely depends on macrophage phenotypes and functionalities. We describe participation of monocytes, monocyte-derived and resident lung macrophages in SARS-CoV-2-associated ARDS and discuss possible utility of cell therapies for its treatment, notably the use of reprogrammed macrophages with stable pro- or anti-inflammatory phenotypes.
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Affiliation(s)
- Anna Kosyreva
- Department of Neuromorphology, Science Research Institute of Human Morphology, Moscow, Russia
- Histology Department, Peoples Friendship University of Russia (RUDN University), Moscow, Russia
| | - Dzhuliia Dzhalilova
- Department of Immunomorphology of Inflammation, Science Research Institute of Human Morphology, Moscow, Russia
| | - Anastasia Lokhonina
- Histology Department, Peoples Friendship University of Russia (RUDN University), Moscow, Russia
- Department of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named After Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
| | - Polina Vishnyakova
- Histology Department, Peoples Friendship University of Russia (RUDN University), Moscow, Russia
- Department of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named After Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
| | - Timur Fatkhudinov
- Histology Department, Peoples Friendship University of Russia (RUDN University), Moscow, Russia
- Department of Growth and Development, Science Research Institute of Human Morphology, Moscow, Russia
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5
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Paris AJ, Hayer KE, Oved JH, Avgousti DC, Toulmin SA, Zepp JA, Zacharias WJ, Katzen JB, Basil MC, Kremp MM, Slamowitz AR, Jayachandran S, Sivakumar A, Dai N, Wang P, Frank DB, Eisenlohr LC, Cantu E, Beers MF, Weitzman MD, Morrisey EE, Worthen GS. STAT3-BDNF-TrkB signalling promotes alveolar epithelial regeneration after lung injury. Nat Cell Biol 2020; 22:1197-1210. [PMID: 32989251 PMCID: PMC8167437 DOI: 10.1038/s41556-020-0569-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/03/2020] [Indexed: 01/13/2023]
Abstract
Alveolar epithelial regeneration is essential for recovery from devastating lung diseases. This process occurs when type II alveolar pneumocytes (AT2 cells) proliferate and transdifferentiate into type I alveolar pneumocytes (AT1 cells). We used genome-wide analysis of chromatin accessibility and gene expression following acute lung injury to elucidate repair mechanisms. AT2 chromatin accessibility changed substantially following injury to reveal STAT3 binding motifs adjacent to genes that regulate essential regenerative pathways. Single-cell transcriptome analysis identified brain-derived neurotrophic factor (Bdnf) as a STAT3 target gene with newly accessible chromatin in a unique population of regenerating AT2 cells. Furthermore, the BDNF receptor tropomyosin receptor kinase B (TrkB) was enriched on mesenchymal alveolar niche cells (MANCs). Loss or blockade of AT2-specific Stat3, Bdnf or mesenchyme-specific TrkB compromised repair and reduced Fgf7 expression by niche cells. A TrkB agonist improved outcomes in vivo following lung injury. These data highlight the biological and therapeutic importance of the STAT3-BDNF-TrkB axis in orchestrating alveolar epithelial regeneration.
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Affiliation(s)
- Andrew J Paris
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Katharina E Hayer
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Joseph H Oved
- Division of Hematology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Daphne C Avgousti
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Sushila A Toulmin
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jarod A Zepp
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - William J Zacharias
- Division of Pulmonary Biology, Perinatal Institute, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Jeremy B Katzen
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Maria C Basil
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Madison M Kremp
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Sowmya Jayachandran
- Division of Cardiology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Aravind Sivakumar
- Division of Cardiology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ning Dai
- Division of Neonatology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ping Wang
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David B Frank
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Cardiology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Laurence C Eisenlohr
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Protective Immunity, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Edward Cantu
- Division of Cardiovascular Surgery, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael F Beers
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Matthew D Weitzman
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Protective Immunity, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Edward E Morrisey
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Institute for Regenerative Medicine, Perelman School of Medicine, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - G Scott Worthen
- Penn-CHOP Lung Biology Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Division of Neonatology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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6
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Spoorenberg SMC, Vestjens SMT, Voorn GP, van Moorsel CHM, Meek B, Zanen P, Rijkers GT, Bos WJW, Grutters JC. Course of SP-D, YKL-40, CCL18 and CA 15-3 in adult patients hospitalised with community-acquired pneumonia and their association with disease severity and aetiology: A post-hoc analysis. PLoS One 2018; 13:e0190575. [PMID: 29324810 PMCID: PMC5764260 DOI: 10.1371/journal.pone.0190575] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 11/23/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND AIM SP-D, YKL-40, CCL18 and CA 15-3 are pulmonary markers that have been extensively investigated in different chronic pulmonary diseases. However, in acute pulmonary diseases, such as community-acquired pneumonia (CAP), little is known about the course of these markers and their relationship with the aetiological agent. The aim of this study was to investigate the course of these four markers in CAP and to study influence of disease severity, aetiology and antibiotic use prior to admission on their course. METHODS We included 291 adult patients hospitalised with CAP and 20 healthy controls. Measurements were performed in serum of day 0, 2, and 4, and at least 30 days after admission. RESULTS Our most important results were: 1) At all time-points, including 30 days after admission, YKL-40 and CCL18 levels were higher in CAP patients compared to healthy controls; and 2) Patients with CAP caused by an intracellular, atypical bacterium had lower YKL-40 and especially CCL18 levels on and during admission in comparison with other or unknown CAP aetiology. CONCLUSIONS Our findings suggest that these pulmonary markers could be useful to assess CAP severity and, especially YKL-40 and CCL18 by helping predict CAP caused by atypical pathogens.
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Affiliation(s)
| | | | - G. P. Voorn
- Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, The Netherlands
| | - Coline H. M. van Moorsel
- Department of Pulmonology, St Antonius Hospital, Nieuwegein, The Netherlands
- Division of Heart and Lungs, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Bob Meek
- Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, The Netherlands
| | - Pieter Zanen
- Division of Heart and Lungs, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Ger T. Rijkers
- Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, The Netherlands
- Department of Sciences, Roosevelt Academy, Middelburg, The Netherlands
| | - Willem Jan W. Bos
- Department of Internal Medicine, St Antonius Hospital, Nieuwegein, The Netherlands
| | - Jan C. Grutters
- Department of Pulmonology, St Antonius Hospital, Nieuwegein, The Netherlands
- Division of Heart and Lungs, University Medical Centre Utrecht, Utrecht, The Netherlands
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7
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Spoorenberg SMC, Vestjens SMT, Rijkers GT, Meek B, van Moorsel CHM, Grutters JC, Bos WJW. YKL-40, CCL18 and SP-D predict mortality in patients hospitalized with community-acquired pneumonia. Respirology 2016; 22:542-550. [PMID: 27782361 DOI: 10.1111/resp.12924] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 08/08/2016] [Accepted: 08/08/2016] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVE The aim of this study was to investigate the prognostic value of four biomarkers, YKL-40, chemokine (C-C motif) ligand 18 (CCL18), surfactant protein-D (SP-D) and CA 15-3, in patients admitted with community-acquired pneumonia (CAP). These markers have been studied extensively in chronic pulmonary disease, but in acute pulmonary disease their prognostic value is unknown. METHODS A total of 289 adult patients who were hospitalized with CAP and participated in a randomized controlled trial were enrolled. Biomarker levels were measured on the day of admission. Intensive care unit admission, 30-day, 1-year and long-term mortality (median follow-up of 5.4 years, interquartile range (IQR): 4.7-6.1) were recorded as outcomes. RESULTS Median YKL-40 and CCL18 levels were significantly higher and levels of SP-D were significantly lower in CAP patients compared to healthy controls. Significantly higher YKL-40, CCL18 and SP-D levels were found in patients classified in pneumonia severity index classes 4-5 and with a CURB-65 score ≥2 compared to patients with less severe pneumonia. Furthermore, these three markers were significant predictors for long-term mortality in multivariate analysis and compared with C-reactive protein and procalcitonin level on admission, area under the curves were higher for 30-day, 1-year and long-term mortality. CA 15-3 levels were less predictive. CONCLUSION YKL-40, CCL18 and SP-D levels were higher in patients with more severe pneumonia, possibly reflecting the extent of pulmonary inflammation. Of these, YKL-40 most significantly predicts mortality for CAP.
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Affiliation(s)
| | - Stefan M T Vestjens
- Department of Internal Medicine, St Antonius Hospital, Nieuwegein, The Netherlands
| | - Ger T Rijkers
- Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, The Netherlands.,Department of Sciences, University College Roosevelt, Middelburg, The Netherlands
| | - Bob Meek
- Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, The Netherlands
| | - Coline H M van Moorsel
- Department of Pulmonology, St Antonius Hospital, Nieuwegein, The Netherlands.,Division of Heart and Lungs, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Jan C Grutters
- Department of Pulmonology, St Antonius Hospital, Nieuwegein, The Netherlands.,Division of Heart and Lungs, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Willem Jan W Bos
- Department of Internal Medicine, St Antonius Hospital, Nieuwegein, The Netherlands
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8
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Paris AJ, Liu Y, Mei J, Dai N, Guo L, Spruce LA, Hudock KM, Brenner JS, Zacharias WJ, Mei HD, Slamowitz AR, Bhamidipati K, Beers MF, Seeholzer SH, Morrisey EE, Worthen GS. Neutrophils promote alveolar epithelial regeneration by enhancing type II pneumocyte proliferation in a model of acid-induced acute lung injury. Am J Physiol Lung Cell Mol Physiol 2016; 311:L1062-L1075. [PMID: 27694472 PMCID: PMC5206401 DOI: 10.1152/ajplung.00327.2016] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 09/25/2016] [Indexed: 12/18/2022] Open
Abstract
Alveolar epithelial regeneration is essential for resolution of the acute respiratory distress syndrome (ARDS). Although neutrophils have traditionally been considered mediators of epithelial damage, recent studies suggest they promote type II pneumocyte (AT2) proliferation, which is essential for regenerating alveolar epithelium. These studies did not, however, evaluate this relationship in an in vivo model of alveolar epithelial repair following injury. To determine whether neutrophils influence alveolar epithelial repair in vivo, we developed a unilateral acid injury model that creates a severe yet survivable injury with features similar to ARDS. Mice that received injections of the neutrophil-depleting Ly6G antibody had impaired AT2 proliferation 24 and 72 h after acid instillation, which was associated with decreased reepithelialization and increased alveolar protein concentration 72 h after injury. As neutrophil depletion itself may alter the cytokine response, we questioned the contribution of neutrophils to alveolar epithelial repair in neutropenic granulocyte-colony stimulating factor (G-CSF)-/- mice. We found that the loss of G-CSF recapitulated the neutrophil response of Ly6G-treated mice and was associated with defective alveolar epithelial repair, similar to neutrophil-depleted mice, and was reversed by administration of exogenous G-CSF. To approach the mechanisms, we employed an unbiased protein analysis of bronchoalveolar lavage fluid from neutrophil-depleted and neutrophil-replete mice 12 h after inducing lung injury. Pathway analysis identified significant differences in multiple signaling pathways that may explain the differences in epithelial repair. These data emphasize an important link between the innate immune response and tissue repair in which neutrophils promote alveolar epithelial regeneration.
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Affiliation(s)
- Andrew J Paris
- Division of Pulmonary, Allergy, and Critical Care Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Yuhong Liu
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Junjie Mei
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ning Dai
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Lei Guo
- Department of Viral Immunology, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Lynn A Spruce
- Department of Pathology and Laboratory Medicine, Cell Pathology Division, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Kristin M Hudock
- Division of Pulmonary, Allergy, and Critical Care Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Division of Pulmonary, Critical Care and Sleep Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Jacob S Brenner
- Division of Pulmonary, Allergy, and Critical Care Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - William J Zacharias
- Division of Pulmonary, Allergy, and Critical Care Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hankun D Mei
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Kartik Bhamidipati
- Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michael F Beers
- Division of Pulmonary, Allergy, and Critical Care Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,The Penn Center for Pulmonary Biology, Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Steven H Seeholzer
- Department of Pathology and Laboratory Medicine, Cell Pathology Division, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Edward E Morrisey
- Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,The Penn Center for Pulmonary Biology, Perelman School of Medicine, Philadelphia, Pennsylvania.,Department of Cell and Developmental Biology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and.,Penn Institute of Regenerative Medicine, Perelman School of Medicine, Philadelphia, Pennsylvania
| | - G Scott Worthen
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; .,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,The Penn Center for Pulmonary Biology, Perelman School of Medicine, Philadelphia, Pennsylvania
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9
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Maier BB, Hladik A, Lakovits K, Korosec A, Martins R, Kral JB, Mesteri I, Strobl B, Müller M, Kalinke U, Merad M, Knapp S. Type I interferon promotes alveolar epithelial type II cell survival during pulmonary Streptococcus pneumoniae infection and sterile lung injury in mice. Eur J Immunol 2016; 46:2175-86. [PMID: 27312374 DOI: 10.1002/eji.201546201] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 05/17/2016] [Accepted: 06/13/2016] [Indexed: 12/22/2022]
Abstract
Protecting the integrity of the lung epithelial barrier is essential to ensure respiration and proper oxygenation in patients suffering from various types of lung inflammation. Type I interferon (IFN-I) has been associated with pulmonary epithelial barrier function, however, the mechanisms and involved cell types remain unknown. We aimed to investigate the importance of IFN-I with respect to its epithelial barrier strengthening function to better understand immune-modulating effects in the lung with potential medical implications. Using a mouse model of pneumococcal pneumonia, we revealed that IFN-I selectively protects alveolar epithelial type II cells (AECII) from inflammation-induced cell death. Mechanistically, signaling via the IFN-I receptor on AECII is sufficient to promote AECII survival. The net effects of IFN-I are barrier protection, together with diminished tissue damage, inflammation, and bacterial loads. Importantly, we found that the protective role of IFN-I can also apply to sterile acute lung injury, in which loss of IFN-I signaling leads to a significant reduction in barrier function caused by AECII cell death. Our data suggest that IFN-I is an important mediator in lung inflammation that plays a protective role by antagonizing inflammation-associated cell obstruction, thereby strengthening the integrity of the epithelial barrier.
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Affiliation(s)
- Barbara B Maier
- CeMM - Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Laboratory of Infection Biology, Department of Medicine I, Medical University, Vienna, Austria
| | - Anastasiya Hladik
- Laboratory of Infection Biology, Department of Medicine I, Medical University, Vienna, Austria
| | - Karin Lakovits
- Laboratory of Infection Biology, Department of Medicine I, Medical University, Vienna, Austria
| | - Ana Korosec
- CeMM - Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Laboratory of Infection Biology, Department of Medicine I, Medical University, Vienna, Austria
| | - Rui Martins
- CeMM - Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Laboratory of Infection Biology, Department of Medicine I, Medical University, Vienna, Austria
| | - Julia B Kral
- Center for Physiology and Pharmacology, Institute for Physiology, Medical University of Vienna, Vienna, Austria
| | | | - Birgit Strobl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine, Vienna, Austria
| | - Mathias Müller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine, Vienna, Austria
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, Helmholtz Center for Infection Research, Braunschweig, Germany.,Hannover Medical School, Hannover, Germany
| | - Miriam Merad
- Department of Oncological Science, The Tisch Cancer Institute and the Immunology Institute, Mount Sinai School of Medicine, New York, New York
| | - Sylvia Knapp
- CeMM - Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria. .,Laboratory of Infection Biology, Department of Medicine I, Medical University, Vienna, Austria.
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10
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Wang LL, Zheng SY, Ren L, Xiao QY, Long XR, Luo J, Li QB, Deng Y, Xie XH, Liu EM. [Levels of surfactant proteins A and D in bronchoalveolar lavage fluid of children with pneumonia and their relationships with clinical characteristics]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2016; 18:386-390. [PMID: 27165584 PMCID: PMC7390360 DOI: 10.7499/j.issn.1008-8830.2016.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 03/04/2016] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To observe the levels of pulmonary surfactant proteins A and D (SP-A, SP-D) in bronchoalveolar lavage fluid (BALF) of children with pneumonia, and to explore their relationships with clinical characteristics. METHODS Thirty-five children with pneumonia were enrolled in this study. Differential cell counts were obtained by Countstar counting board. The levels of SP-A and SP-D in BALF were detected using ELISA. RESULTS In children with pneumonia, SP-D levels were significantly higher than SP-A levels (P<0.001). SP-D levels were negatively correlated with the neutrophil percentage in BALF (r(s)=-0.5255, P<0.01). SP-D levels in BALF in children with increased blood C-reactive protein levels (>8 mg/L) were significantly lower than in those with a normal level of C-reactive protein (P<0.05). Compared with those in children without wheezing, SP-D levels in children with wheezing were significantly lower (P<0.01). There was no correlation between SP-A levels and clinical characteristics. CONCLUSIONS SP-D levels in BALF are significantly higher than SP-A levels, and have a certain correlation with clinical characteristics in children with pneumonia. As a protective factor, SP-D plays a more important role than SP-A in regulating the immune and inflammatory responses.
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Affiliation(s)
- Li-Li Wang
- Pediatric Research Institute of Children's Hospital of Chongqing Medical University, Chongqing 400014, China.
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11
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Wu F, Jordan A, Kluz T, Shen S, Sun H, Cartularo LA, Costa M. SATB2 expression increased anchorage-independent growth and cell migration in human bronchial epithelial cells. Toxicol Appl Pharmacol 2016; 293:30-6. [PMID: 26780400 DOI: 10.1016/j.taap.2016.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 01/05/2016] [Accepted: 01/08/2016] [Indexed: 12/25/2022]
Abstract
The special AT-rich sequence-binding protein 2 (SATB2) is a protein that binds to the nuclear matrix attachment region of the cell and regulates gene expression by altering chromatin structure. In our previous study, we reported that SATB2 gene expression was induced in human bronchial epithelial BEAS-2B cells transformed by arsenic, chromium, nickel and vanadium. In this study, we show that ectopic expression of SATB2 in the normal human bronchial epithelial cell-line BEAS-2B increased anchorage-independent growth and cell migration, meanwhile, shRNA-mediated knockdown of SATB2 significantly decreased anchorage-independent growth in Ni transformed BEAS-2B cells. RNA sequencing analyses of SATB2 regulated genes revealed the enrichment of those involved in cytoskeleton, cell adhesion and cell-movement pathways. Our evidence supports the hypothesis that SATB2 plays an important role in BEAS-2B cell transformation.
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Affiliation(s)
- Feng Wu
- Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
| | - Ashley Jordan
- Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
| | - Thomas Kluz
- Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
| | - Steven Shen
- Center for Health Informatics and Bioinformatics, New York University Langone Medical Center, New York, NY 10016, USA
| | - Hong Sun
- Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
| | - Laura A Cartularo
- Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
| | - Max Costa
- Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA.
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12
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Castillo RL, Carrasco Loza R, Romero-Dapueto C. Pathophysiological Approaches of Acute Respiratory Distress syndrome: Novel Bases for Study of Lung Injury. Open Respir Med J 2015; 9:83-91. [PMID: 26312099 PMCID: PMC4541465 DOI: 10.2174/1874306401509010083] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Revised: 04/16/2015] [Accepted: 04/16/2015] [Indexed: 12/22/2022] Open
Abstract
Experimental approaches have been implemented to research the lung damage related-mechanism. These models show in animals pathophysiological events for acute respiratory distress syndrome (ARDS), such as neutrophil activation, reactive oxygen species burst, pulmonary vascular hypertension, exudative edema, and other events associated with organ dysfunction. Moreover, these approaches have not reproduced the clinical features of lung damage. Lung inflammation is a relevant event in the develop of ARDS as component of the host immune response to various stimuli, such as cytokines, antigens and endotoxins. In patients surviving at the local inflammatory states, transition from injury to resolution is an active mechanism regulated by the immuno-inflammatory signaling pathways. Indeed, inflammatory process is regulated by the dynamics of cell populations that migrate to the lung, such as neutrophils and on the other hand, the role of the modulation of transcription factors and reactive oxygen species (ROS) sources, such as nuclear factor kappaB and NADPH oxidase. These experimental animal models reproduce key components of the injury and resolution phases of human ALI/ARDS and provide a methodology to explore mechanisms and potential new therapies.
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Affiliation(s)
- R L Castillo
- Programa de Fisiopatología, Facultad de Medicina, Universidad de Chile, Chile
| | - R Carrasco Loza
- Departamento de Medicina, Hospital del Salvador, Santiago, Chile; Laboratorio de Investigación Biomédica, Hospital del Salvador, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - C Romero-Dapueto
- Servicio de Medicina Física y Rehabilitación, Clínica Alemana de Santiago, Santiago, Chile
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13
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Lin L, Wen SH, Guo SZ, Su XY, Wu HJ, Chong L, Zhang HL, Zhang WX, Li CC. Role of SIRT1 in Streptococcus pneumoniae-induced human β-defensin-2 and interleukin-8 expression in A549 cell. Mol Cell Biochem 2014; 394:199-208. [PMID: 24894820 DOI: 10.1007/s11010-014-2095-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 05/15/2014] [Indexed: 12/19/2022]
Abstract
Streptococcus pneumoniae is an important pathogen of pneumonia in human. Human alveolar epithelium acts as an effective barrier and is an active participant in host defense against invasion of bacterial by production of various mediators. Sirtuin 1 (SIRT1), the prototypic class III histone deacetylase, is involved in the molecular control of lifespans and immune responses. This study aimed at examining the role of SIRT1 in mediating S. pneumoniae-induced human β-defensin-2 (hBD2) and interleukin-8(IL-8) expression in the alveolar epithelial cell line A549 and the underlying mechanisms involved. A549 cells were infected with S. pneumoniae for indicated times. Exposure of A549 cells to S. pneumoniae increased the expressions of SIRT1 protein, hBD2 and IL-8 mRNA, and protein. The SIRT1 activator resveratrol enhanced S. pneumoniae-induced gene expression of hBD2 but decreased IL-8 mRNA levels. Blockade of SIRT1 activity by the SIRT1 inhibitors nicotinamide reduced S. pneumoniae-induced hBD2 mRNA expression but increased its stimulatory effects on IL-8 mRNA. S. pneumoniae-induced activation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK). SIRT1 expression was attenuated by selective inhibitors of ERK and p38 MAPK. The hBD2 mRNA production was decreased by pretreatment with p38 MAPK inhibitor but not with ERK inhibitor, whereas the IL-8 mRNA expression was controlled by phosphorylation of ERK. These results suggest that SIRT1 mediates the induction of hBD2 and IL-8 gene expression levels in A549 cell by S. pneumoniae. SIRT1 may play a key role in host immune and defense response in A549.
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Affiliation(s)
- Li Lin
- Department of Pediatric Pulmonology, The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, 109 West Xueyuan Road, Lucheng District, Wenzhou, 325027, Zhejiang, People's Republic of China
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14
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Henderson WR, Barnbrook J, Dominelli PB, Griesdale DE, Arndt T, Molgat-Seon Y, Foster G, Ackland GL, Xu J, Ayas NT, Sheel AW. Administration of intrapulmonary sodium polyacrylate to induce lung injury for the development of a porcine model of early acute respiratory distress syndrome. Intensive Care Med Exp 2014; 2:5. [PMID: 26266906 PMCID: PMC4513039 DOI: 10.1186/2197-425x-2-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 01/10/2014] [Indexed: 12/15/2022] Open
Abstract
Background The loss of alveolar epithelial and endothelial integrity is a central component in acute respiratory distress syndrome (ARDS); however, experimental models investigating the mechanisms of epithelial injury are lacking. The purpose of the present study was to design and develop an experimental porcine model of ARDS by inducing lung injury with intrapulmonary administration of sodium polyacrylate (SPA). Methods The present study was performed at the Centre for Comparative Medicine, University of British Columbia, Vancouver, British Columbia. Human alveolar epithelial cells were cultured with several different concentrations of SPA; a bioluminescence technique was used to assess cell death associated with each concentration. In the anesthetized pig model (female Yorkshire X pigs (n = 14)), lung injury was caused in 11 animals (SPA group) by injecting sequential aliquots (5 mL) of 1% SPA gel in aqueous solution into the distal airway via a rubber catheter through an endotracheal tube. The SPA was dispersed throughout the lungs by manual bag ventilation. Three control animals (CON group) underwent all experimental procedures and measurements with the exception of SPA administration. Results The mean (± SD) ATP concentration after incubation of human alveolar epithelial cells with 0.1% SPA (0.92 ± 0.27 μM/well) was approximately 15% of the value found for the background control (6.30 ± 0.37 μM/well; p < 0.001). Elastance of the respiratory system (ERS) and the lung (EL) increased in SPA-treated animals after injury (p = 0.003 and p < 0.001, respectively). Chest wall elastance (ECW) did not change in SPA-treated animals. There were no differences in ERS,EL, or ECW in the CON group when pre- and post-injury values were compared. Analysis of bronchoalveolar lavage fluid showed a significant shift toward neutrophil predominance from before to after injury in SPA-treated animals (p < 0.001) but not in the CON group (p = 0.38). Necropsy revealed marked consolidation and congestion of the dorsal lung lobes in SPA-treated animals, with light-microscopy evidence of bronchiolar and alveolar spaces filled with neutrophilic infiltrate, proteinaceous debris, and fibrin deposition. These findings were absent in animals in the CON group. Electron microscopy of lung tissue from SPA-treated animals revealed injury to the alveolar epithelium and basement membranes, including intra-alveolar neutrophils and fibrin on the alveolar surface and intravascular fibrin (microthrombosis). Conclusions In this particular porcine model, the nonimmunogenic polymer SPA caused a rapid exudative lung injury. This model may be useful to study ARDS caused by epithelial injury and inflammation.
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Affiliation(s)
- William R Henderson
- Wolfson Institute for Biomedical Research, Department of Medicine, University College London, London, WC1E 6BT, UK,
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