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Gandhi NN, Inzana TJ, Rajagopalan P. Bovine Airway Models: Approaches for Investigating Bovine Respiratory Disease. ACS Infect Dis 2023; 9:1168-1179. [PMID: 37257116 DOI: 10.1021/acsinfecdis.2c00618] [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] [Indexed: 06/02/2023]
Abstract
Bovine respiratory disease (BRD) is a multifactorial condition where different genera of bacteria, such as Mannheimia haemolytica, Histophilus somni, Pasteurella multocida, and Mycoplasma bovis, and viruses, like bovine respiratory syncytial virus, bovine viral diarrhea virus, and bovine herpes virus-1, infect the lower respiratory tract of cattle. These pathogens can co-infect cells in the respiratory system, thereby making specific treatment very difficult. Currently, the most common models for studying BRD include a submerged tissue culture (STC), where monolayers of epithelial cells are typically covered either in cellular or spent biofilm culture medium. Another model is an air-liquid interface (ALI), where epithelial cells are exposed on their apical side and allowed to differentiate. However, limited work has been reported on the study of three-dimensional (3D) bovine models that incorporate multiple cell types to represent the architecture of the respiratory tract. The roles of different defense mechanisms in an infected bovine respiratory system, such as mucin production, tight junction barriers, and the production of antimicrobial peptides in in vitro cultures require further investigation in order to provide a comprehensive understanding of the disease pathogenesis. In this report, we describe the different aspects of BRD, including the most implicated pathogens and the respiratory tract, which are important to incorporate in disease models assembled in vitro. Although current advancements of bovine respiratory cultures have led to knowledge of the disease, 3D multicellular organoids that better recapitulate the in vivo environment exhibit potential for future investigations.
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Affiliation(s)
- Neeti N Gandhi
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Thomas J Inzana
- College of Veterinary Medicine, Long Island University, Brookville, New York 11548, United States
| | - Padmavathy Rajagopalan
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
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2
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Preliminary Study on the Development of In Vitro Human Respiratory Epithelium Using Collagen Type I Scaffold as a Potential Model for Future Tracheal Tissue Engineering. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11041787] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Pathological conditions of the tracheal epithelium, such as postoperative injuries and chronic conditions, often compromise the functionality of the respiratory epithelium. Although replacement of the respiratory epithelium using various types of tracheal transplantation has been attempted, there is no predictable and dependable replacement method that holds for safe and practicable long-term use. Therefore, we used a tissue engineering approach for ex vivo regeneration of the respiratory epithelium (RE) construct. Collagen type I was isolated from sheep tendon and it was fabricated in a three-dimensional (3D) scaffold format. Isolated human respiratory epithelial cells (RECs) and fibroblasts from nasal turbinate were co-cultured on the 3D scaffold for 48 h, and epithelium maturation was allowed for another 14 days in an air–liquid interface culture system. The scanning electron microscope results revealed a fabricated porous-structure 3D collagen scaffold. The scaffold was found to be biocompatible with RECs and fibroblasts and allows cells attachment, proliferation, and migration. Immunohistochemical analysis showed that the seeded RECs and fibroblasts were positive for expression of cytokeratin 14 and collagen type I markers, respectively, indicating that the scaffold supports the native phenotype of seeded cells over a period of 14 days. Although a longer maturation period is needed for ciliogenesis to occur in RECs, the findings suggest that the tissue-engineered RE construct is a potential candidate for direct use in tracheal epithelium replacement or tracheal tube reengineering.
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3
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Optimizations of In Vitro Mucus and Cell Culture Models to Better Predict In Vivo Gene Transfer in Pathological Lung Respiratory Airways: Cystic Fibrosis as an Example. Pharmaceutics 2020; 13:pharmaceutics13010047. [PMID: 33396283 PMCID: PMC7823756 DOI: 10.3390/pharmaceutics13010047] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/22/2020] [Accepted: 12/28/2020] [Indexed: 11/17/2022] Open
Abstract
The respiratory epithelium can be affected by many diseases that could be treated using aerosol gene therapy. Among these, cystic fibrosis (CF) is a lethal inherited disease characterized by airways complications, which determine the life expectancy and the effectiveness of aerosolized treatments. Beside evaluations performed under in vivo settings, cell culture models mimicking in vivo pathophysiological conditions can provide complementary insights into the potential of gene transfer strategies. Such models must consider multiple parameters, following the rationale that proper gene transfer evaluations depend on whether they are performed under experimental conditions close to pathophysiological settings. In addition, the mucus layer, which covers the epithelial cells, constitutes a physical barrier for gene delivery, especially in diseases such as CF. Artificial mucus models featuring physical and biological properties similar to CF mucus allow determining the ability of gene transfer systems to effectively reach the underlying epithelium. In this review, we describe mucus and cellular models relevant for CF aerosol gene therapy, with a particular emphasis on mucus rheology. We strongly believe that combining multiple pathophysiological features in single complex cell culture models could help bridge the gaps between in vitro and in vivo settings, as well as viral and non-viral gene delivery strategies.
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Choice of Differentiation Media Significantly Impacts Cell Lineage and Response to CFTR Modulators in Fully Differentiated Primary Cultures of Cystic Fibrosis Human Airway Epithelial Cells. Cells 2020; 9:cells9092137. [PMID: 32967385 PMCID: PMC7565948 DOI: 10.3390/cells9092137] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/13/2020] [Accepted: 09/16/2020] [Indexed: 12/13/2022] Open
Abstract
In vitro cultures of primary human airway epithelial cells (hAECs) grown at air–liquid interface have become a valuable tool to study airway biology under normal and pathologic conditions, and for drug discovery in lung diseases such as cystic fibrosis (CF). An increasing number of different differentiation media, are now available, making comparison of data between studies difficult. Here, we investigated the impact of two common differentiation media on phenotypic, transcriptomic, and physiological features of CF and non-CF epithelia. Cellular architecture and density were strongly impacted by the choice of medium. RNA-sequencing revealed a shift in airway cell lineage; one medium promoting differentiation into club and goblet cells whilst the other enriched the growth of ionocytes and multiciliated cells. Pathway analysis identified differential expression of genes involved in ion and fluid transport. Physiological assays (intracellular/extracellular pH, Ussing chamber) specifically showed that ATP12A and CFTR function were altered, impacting pH and transepithelial ion transport in CF hAECs. Importantly, the two media differentially affected functional responses to CFTR modulators. We argue that the effect of growth conditions should be appropriately determined depending on the scientific question and that our study can act as a guide for choosing the optimal growth medium for specific applications.
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5
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Luengen AE, Kniebs C, Buhl EM, Cornelissen CG, Schmitz-Rode T, Jockenhoevel S, Thiebes AL. Choosing the Right Differentiation Medium to Develop Mucociliary Phenotype of Primary Nasal Epithelial Cells In Vitro. Sci Rep 2020; 10:6963. [PMID: 32332878 PMCID: PMC7181704 DOI: 10.1038/s41598-020-63922-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/06/2020] [Indexed: 11/08/2022] Open
Abstract
In vitro differentiation of airway epithelium is of interest for respiratory tissue engineering and studying airway diseases. Both applications benefit from the use of primary cells to maintain a mucociliated phenotype and thus physiological functionality. Complex differentiation procedures often lack standardization and reproducibility. To alleviate these shortfalls, we compared differentiation behavior of human nasal epithelial cells in four differentiation media. Cells were differentiated at the air-liquid interface (ALI) on collagen-coated inserts. Mucociliary differentiation status after five weeks was analyzed by electron microscopy, histology and immunohistochemistry. The amount of ciliation was estimated and growth factor concentrations were evaluated using ELISA. We found that retinoic-acid-supplemented mixture of DMEM and Airway Epithelial Cell Growth Medium gave most promising results to obtain ciliated and mucus producing nasal epithelium in vitro. We discovered the balance between retinoic acid (RA), vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and fibroblast growth factor β (FGF-β) to be relevant for differentiation. We could show that low VEGF, EGF and FGF-β concentrations in medium correspond to absent ciliation in specific donors. Therefore, our results may in future facilitate donor selection and non-invasive monitoring of ALI cultures and by this contribute to improved standardization of epithelial in vitro culture.
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Affiliation(s)
- Anja E Luengen
- Department of Biohybrid and Medical Textiles (BioTex), AME - Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Forckenbeckstraße 55, 52074, Aachen, Germany.
- Aachen-Maastricht Institute for Biobased Materials, Faculty of Science and Engineering, Maastricht University, Brightlands Chemelot Campus, 6167 RD, Geleen, The Netherlands.
| | - Caroline Kniebs
- Department of Biohybrid and Medical Textiles (BioTex), AME - Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Forckenbeckstraße 55, 52074, Aachen, Germany
- Aachen-Maastricht Institute for Biobased Materials, Faculty of Science and Engineering, Maastricht University, Brightlands Chemelot Campus, 6167 RD, Geleen, The Netherlands
| | - Eva Miriam Buhl
- Institute of Pathology, Electron Microscopy Facility, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Christian G Cornelissen
- Department of Biohybrid and Medical Textiles (BioTex), AME - Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Forckenbeckstraße 55, 52074, Aachen, Germany
- Clinic for Pneumology and Internal Intensive Care Medicine (Medical Clinic V), RWTH Aachen University Hospital, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Thomas Schmitz-Rode
- Department of Biohybrid and Medical Textiles (BioTex), AME - Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Forckenbeckstraße 55, 52074, Aachen, Germany
| | - Stefan Jockenhoevel
- Department of Biohybrid and Medical Textiles (BioTex), AME - Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Forckenbeckstraße 55, 52074, Aachen, Germany.
- Aachen-Maastricht Institute for Biobased Materials, Faculty of Science and Engineering, Maastricht University, Brightlands Chemelot Campus, 6167 RD, Geleen, The Netherlands.
| | - Anja Lena Thiebes
- Department of Biohybrid and Medical Textiles (BioTex), AME - Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Forckenbeckstraße 55, 52074, Aachen, Germany
- Aachen-Maastricht Institute for Biobased Materials, Faculty of Science and Engineering, Maastricht University, Brightlands Chemelot Campus, 6167 RD, Geleen, The Netherlands
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6
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Kreimendahl F, Ossenbrink S, Köpf M, Westhofen M, Schmitz‐Rode T, Fischer H, Jockenhoevel S, Thiebes AL. Combination of vascularization and cilia formation for three‐dimensional airway tissue engineering. J Biomed Mater Res A 2019; 107:2053-2062. [DOI: 10.1002/jbm.a.36718] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/30/2019] [Accepted: 05/07/2019] [Indexed: 11/12/2022]
Affiliation(s)
- Franziska Kreimendahl
- Department of Biohybrid and Medical Textiles (BioTex), AME ‐ Institute of Applied Medical Engineering, Helmholtz InstituteRWTH Aachen University Aachen Germany
| | - Sina Ossenbrink
- Department of Biohybrid and Medical Textiles (BioTex), AME ‐ Institute of Applied Medical Engineering, Helmholtz InstituteRWTH Aachen University Aachen Germany
| | - Marius Köpf
- Department of Dental Materials and Biomaterials ResearchRWTH Aachen University Hospital Aachen Germany
| | - Martin Westhofen
- Clinic for Otorhinolaryngology and Plastic Surgery of the Head and ThroatRWTH Aachen University Hospital Aachen Germany
| | - Thomas Schmitz‐Rode
- Department of Biohybrid and Medical Textiles (BioTex), AME ‐ Institute of Applied Medical Engineering, Helmholtz InstituteRWTH Aachen University Aachen Germany
| | - Horst Fischer
- Department of Dental Materials and Biomaterials ResearchRWTH Aachen University Hospital Aachen Germany
| | - Stefan Jockenhoevel
- Department of Biohybrid and Medical Textiles (BioTex), AME ‐ Institute of Applied Medical Engineering, Helmholtz InstituteRWTH Aachen University Aachen Germany
| | - Anja L. Thiebes
- Department of Biohybrid and Medical Textiles (BioTex), AME ‐ Institute of Applied Medical Engineering, Helmholtz InstituteRWTH Aachen University Aachen Germany
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7
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Huang TW, Li ST, Fang KM, Young TH. Hyaluronan antagonizes the differentiation effect of TGF-β1 on nasal epithelial cells through down-regulation of TGF-β type I receptor. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2018; 46:S254-S263. [PMID: 30032656 DOI: 10.1080/21691401.2018.1491477] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Although hyaluronan (HA)-based biomaterials have been proposed to promote mucociliary differentiation of nasal epithelial cells (NECs), the mechanism by which HA affects the growth and differentiation of NECs has not been thoroughly explored. This study investigates the effect and mechanism of HA on the differentiation of NECs. The experiment cultures human NECs in four conditions, namely controls, transforming growth factor (TGF)-β1, TGF-β1 + HA and HA groups. In the TGF group, the NECs become irregular shape without formation of tight junction and mucociliary differentiation of NECs is inhibited. Epithelial-mesenchymal transition (EMT) of NECs also occurs in the TGF group. However, with addition of HA in TGF groups, NECs reveal the mucociliary phenotypes of epithelial cells with tight junction expression. Incubation of TGF-β1 in an NEC culture leads to an increase in phosphorylated type 1 TGF-β receptors (p-TβRI). This increase is attenuated when NECs are cultured in the presence of HA. Similar expressions are observed in phosphorylated smad2/smad3. Additionally, HA-dependent inhibition of TGF-β1 signalling is inhibited by co-incubation with a blocking antibody to CD44. Experimental results indicate that HA can antagonize TGF-β1 effect on EMT and mucociliary differentiation of NECs by down-regulation of TβR I, which is via CD44.
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Affiliation(s)
- Tsung-Wei Huang
- a Department of Electrical Engineering, College of Electrical and Communication Engineering , Yuan Ze University , Taoyuan , Taiwan.,b Department of Otolaryngology , Far Eastern Memorial Hospital , Taipei , Taiwan.,c Department of Health Care Administration , Oriental Institute of Technology , Taipei , Taiwan
| | - Sheng-Tien Li
- d College of Medicine and College of Engineering , Institute of Biomedical Engineering , National Taiwan University , Taipei , Taiwan
| | - Kai-Min Fang
- b Department of Otolaryngology , Far Eastern Memorial Hospital , Taipei , Taiwan
| | - Tai-Horng Young
- d College of Medicine and College of Engineering , Institute of Biomedical Engineering , National Taiwan University , Taipei , Taiwan
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8
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O’Boyle N, Sutherland E, Berry CC, Davies RL. Optimisation of growth conditions for ovine airway epithelial cell differentiation at an air-liquid interface. PLoS One 2018; 13:e0193998. [PMID: 29518140 PMCID: PMC5843276 DOI: 10.1371/journal.pone.0193998] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 02/22/2018] [Indexed: 11/18/2022] Open
Abstract
Respiratory tract infections are of significant concern in the agriculture industry. There is a requirement for the development of well-characterised in vitro epithelial cell culture models in order to dissect the diverse molecular interactions occurring at the host-pathogen interface in airway epithelia. We have analysed key factors that influence growth and differentiation of ovine tracheal epithelial cells in an air-liquid interface (ALI) culture system. Cellular differentiation was assessed at 21 days post-ALI, a time-point which we have previously shown to be sufficient for differentiation in standard growth conditions. We identified a dose-dependent response to epidermal growth factor (EGF) in terms of both epithelial thickening and ciliation levels. Maximal ciliation levels were observed with 25 ng ml-1 EGF. We identified a strict requirement for retinoic acid (RA) in epithelial differentiation as RA exclusion resulted in the formation of a stratified squamous epithelium, devoid of cilia. The pore-density of the growth substrate also had an influence on differentiation as high pore-density inserts yielded higher levels of ciliation and more uniform cell layers than low pore-density inserts. Differentiation was also improved by culturing the cells in an atmosphere of sub-ambient oxygen concentration. We compared two submerged growth media and observed differences in the rate of proliferation/expansion, barrier formation and also in terminal differentiation. Taken together, these results indicate important differences between the response of ovine tracheal epithelial cells and other previously described airway epithelial models, to a variety of environmental conditions. These data also indicate that the phenotype of ovine tracheal epithelial cells can be tailored in vitro by precise modulation of growth conditions, thereby yielding a customisable, potential infection model.
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Affiliation(s)
- Nicky O’Boyle
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Erin Sutherland
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Catherine C. Berry
- Institute of Molecular Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Robert L. Davies
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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9
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Development and optimization of a differentiated airway epithelial cell model of the bovine respiratory tract. Sci Rep 2018; 8:853. [PMID: 29339818 PMCID: PMC5770467 DOI: 10.1038/s41598-017-19079-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 12/19/2017] [Indexed: 12/14/2022] Open
Abstract
Cattle are subject to economically-important respiratory tract infections by various bacterial and viral pathogens and there is an urgent need for the development of more realistic in vitro models of the bovine respiratory tract to improve our knowledge of disease pathogenesis. In the present study, we have optimized the culture conditions in serum-free medium that allow bovine bronchial epithelial cells (BBECs) grown at an air-liquid interface to differentiate into a three-dimensional epithelium that is highly representative of the bovine airway. Epidermal growth factor was required to trigger both proliferation and differentiation of BBECs whilst retinoic acid was also essential for mucociliary differentiation. Triiodothyronine was demonstrated not to be important for the differentiation of BBECs. Oxygen concentration had a minimal effect although optimal ciliation was achieved when BBECs were cultured at 14% oxygen tension. Insert pore-density had a significant effect on the growth and differentiation of BBECs; a high-pore-density was required to trigger optimum differentiation. The established BBEC model will have wide-ranging applications for the study of bacterial and viral infections of the bovine respiratory tract; it will contribute to the development of improved vaccines and therapeutics and will reduce the use of cattle in in vivo experimentation.
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10
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Al-Sayed AA, Agu RU, Massoud E. Models for the study of nasal and sinus physiology in health and disease: A review of the literature. Laryngoscope Investig Otolaryngol 2017; 2:398-409. [PMID: 29299515 PMCID: PMC5743156 DOI: 10.1002/lio2.117] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/04/2017] [Accepted: 10/02/2017] [Indexed: 12/25/2022] Open
Abstract
Objective Chronic sinusitis is a very common yet poorly understood medical condition with significant morbidity. Hence, it remains an entity that is difficult to treat with unsatisfactory outcomes of current management options. This necessitates research into the etiology and pathophysiology of the condition to enhance our knowledge and the therapeutic options. Unfortunately, this kind of research is not always feasible on human subjects due to practical and ethical limitations. Therefore, an alternative model that simulates the disease had to be found in order to overcome these limitations. These models could either be in vivo or in vitro. The aim of our review is to summarize the research findings and key discoveries of both in vivo and in vitro models of chronic sinusitis that have enhanced our understanding of the condition today and have paved the way for the future research of tomorrow. Data Sources: PubMed literature review. Methods A review of the literature was conducted to identify the main successful in vivo and in vitro models for chronic sinusitis. Results Creating a successful model for chronic sinusitis is no easy task. Over the years, both in vivo animal models and in vitro tissue culture models were proposed, with each model having its accolades and pitfalls, with the ideal model remaining elusive to this day. However, advancing three‐dimensional cell culturing techniques seems to be a promising new way to find a more accurate model. Conclusion None of the current models is perfect for a thorough study of chronic sinusitis. However, three‐dimensional cell cultures have the potential to bridge the gap between in vivo and in vitro studies. Level of Evidence NA
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Affiliation(s)
- Ahmed A Al-Sayed
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine King Saud University Riyadh Kingdom of Saudi Arabia.,Division of Otolaryngology-Head & Neck Surgery, Department of Surgery Dalhousie University Halifax Nova Scotia Canada
| | - Remigius U Agu
- College of Pharmacy Dalhousie University, 5968 College Street, PO Box 1500 Halifax NS B3H4R2 Canada
| | - Emad Massoud
- Division of Otolaryngology-Head & Neck Surgery, Department of Surgery Dalhousie University Halifax Nova Scotia Canada
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11
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LaRanger R, Peters-Hall JR, Coquelin M, Alabi BR, Chen CT, Wright WE, Shay JW. Reconstituting Mouse Lungs with Conditionally Reprogrammed Human Bronchial Epithelial Cells. Tissue Eng Part A 2017; 24:559-568. [PMID: 28726588 DOI: 10.1089/ten.tea.2017.0114] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
We developed methods for conditionally reprogramming (CR) primary human bronchial epithelial cells (HBECs) to extend their functional lifespan and permit their differentiation into both upper and lower airway lung epithelium. We also developed a bioreactor to support vascular perfusion and rhythmic breathing of decellularized mouse lungs reconstituted with CR HBECs isolated from patients with and without cystic fibrosis (CF). While conditionally reprogrammed cells only differentiate into an upper airway epithelium after 35 days at the air-liquid interface, in reconstituted lungs these cells differentiate into upper airway bronchial epithelium and lower airway alveolar structures after 12 days. Rapid scale-up and the ability to obtain clonal derivatives of primary patient-derived HBECs without the need for genetic manipulation may permit rapid reconstitution of the lung epithelium; facilitating the study of lung disease in tissue-engineered models.
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Affiliation(s)
- Ryan LaRanger
- 1 Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Jennifer R Peters-Hall
- 1 Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Melissa Coquelin
- 1 Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Busola R Alabi
- 1 Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Christopher T Chen
- 2 Biomedical Engineering Program, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Woodring E Wright
- 1 Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Jerry W Shay
- 1 Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
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12
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Huang TW, Wei CK, Su HW, Fang KM. Chitosan promotes aquaporin formation and inhibits mucociliary differentiation of nasal epithelial cells through increased TGF-β1 production. J Tissue Eng Regen Med 2016; 11:3567-3575. [PMID: 27804234 DOI: 10.1002/term.2274] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 07/10/2016] [Accepted: 07/19/2016] [Indexed: 01/07/2023]
Abstract
Although endoscopic sinus surgery is the mainstay surgical treatment for chronic rhinosinusitis, over 15% of patients require a repeat operation wherein postoperative adhesion formation is one of the main causes of failure. Several recently proposed chitosan-based biomaterials promote mucosal healing, reduce postoperative adhesion formation and restore mucociliary function of sinonasal mucosa. However, the effects of chitosan on cellular morphology, re-epithelization, and mucociliary differentiation of nasal epithelial cells (NECs) during the wound healing process have not been thoroughly investigated. The present study investigates the direct effects of chitosan on cellular growth, cellular migration, mucociliary differentiation and aquaporin (AQP) formation of NECs to elucidate the role of chitosan in sinonasal applications. Wound healing assay reveals that proliferation and migration of NECs are inhibited by incubation of chitosan. The NECs become irregular in shape without formation of tight junction and mucociliary differentiation of NECs is inhibited during a culture period with incubation of chitosan. However, AQP3 and AQP5 formation in NECs is significantly higher in chitosan groups than in control groups. Further, expressions of transforming growth factor (TGF)-β1, Smad2, and Smad3 are significantly higher in the chitosan groups compared with controls. The results of the comparison indicate that chitosan inhibits proliferation, migration and mucociliary differentiation of NECs through increasing production of TGF-β1. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Tsung-Wei Huang
- Department of Electrical Engineering, Yuan Ze University, Taoyuan, Taiwan.,Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan.,Department of Health Care Administration, Oriental Institute of Technology, Taipei, Taiwan
| | - Ching-Kuo Wei
- Department of Health Care Administration, Oriental Institute of Technology, Taipei, Taiwan
| | - Huang-Wei Su
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan.,Department of Tourism and Leisure Management, Tung-Fang Design University, Kaohsiung, Taiwan
| | - Kai-Min Fang
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan
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13
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Mulay A, Akram KM, Williams D, Armes H, Russell C, Hood D, Armstrong S, Stewart JP, Brown SDM, Bingle L, Bingle CD. An in vitro model of murine middle ear epithelium. Dis Model Mech 2016; 9:1405-1417. [PMID: 27660200 PMCID: PMC5117233 DOI: 10.1242/dmm.026658] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/15/2016] [Indexed: 01/01/2023] Open
Abstract
Otitis media (OM), or middle ear inflammation, is the most common paediatric disease and leads to significant morbidity. Although understanding of underlying disease mechanisms is hampered by complex pathophysiology it is clear that epithelial abnormalities underpin the disease. There is currently a lack of a well-characterised in vitro model of the middle ear (ME) epithelium that replicates the complex cellular composition of the middle ear. Here, we report the development of a novel in vitro model of mouse middle ear epithelial cells (mMECs) at an air–liquid interface (ALI) that recapitulates the characteristics of the native murine ME epithelium. We demonstrate that mMECs undergo differentiation into the varied cell populations seen within the native middle ear. Proteomic analysis confirmed that the cultures secrete a multitude of innate defence proteins from their apical surface. We showed that the mMECs supported the growth of the otopathogen, nontypeable Haemophilus influenzae (NTHi), suggesting that the model can be successfully utilised to study host–pathogen interactions in the middle ear. Overall, our mMEC culture system can help to better understand the cell biology of the middle ear and improve our understanding of the pathophysiology of OM. The model also has the potential to serve as a platform for validation of treatments designed to reverse aspects of epithelial remodelling that underpin OM development. Summary: Development and systematic characterisation of an in vitro otopathogenic infection model of the murine middle ear epithelium as a tool to better understand the complex pathophysiology of Otitis media.
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Affiliation(s)
- Apoorva Mulay
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
| | - Khondoker M Akram
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
| | | | - Hannah Armes
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK.,Oral and Maxillofacial Pathology, Department of Clinical Dentistry, University of Sheffield, Sheffield S10 2TA, UK
| | - Catherine Russell
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
| | - Derek Hood
- MRC Mammalian Genetics Unit, Harwell OX11 0RD, UK
| | - Stuart Armstrong
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L3 5RF, UK
| | - James P Stewart
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L3 5RF, UK
| | | | - Lynne Bingle
- Oral and Maxillofacial Pathology, Department of Clinical Dentistry, University of Sheffield, Sheffield S10 2TA, UK
| | - Colin D Bingle
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
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14
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Min KA, Rosania GR, Shin MC. Human Airway Primary Epithelial Cells Show Distinct Architectures on Membrane Supports Under Different Culture Conditions. Cell Biochem Biophys 2016; 74:191-203. [PMID: 26818810 DOI: 10.1007/s12013-016-0719-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/14/2016] [Indexed: 11/29/2022]
Abstract
To facilitate drug development for lung delivery, it is highly demanding to establish appropriate airway epithelial cell models as transport barriers to evaluate pharmacokinetic profiles of drug molecules. Besides the cancer-derived cell lines, as the primary cell model, normal human bronchial epithelial (NHBE) cells have been used for drug screenings because of physiological relevance to in vivo. Therefore, to accurately interpret drug transport data in NHBE measured by different laboratories, it is important to know biophysical characteristics of NHBE grown on membranes in different culture conditions. In this study, NHBE was grown on the polyester membrane in a different medium and its transport barrier properties as well as cell architectures were fully characterized by functional assays and confocal imaging throughout the days of cultures. Moreover, NHBE cells on inserts in a different medium were subject to either of air-interfaced culture (AIC) or liquid-covered culture (LCC) condition. Cells in the AIC condition were cultivated on the membrane with medium in the basolateral side only, whereas cells with medium in apical and basolateral sides under the LCC condition. Quantitative microscopic imaging with biophysical examination revealed distinct multilayered architectures of differentiated NHBE cells, suggesting NHBE as functional cell barriers for the lung-targeting drug transport.
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Affiliation(s)
- Kyoung Ah Min
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, 501 Jinju Daero, Jinju, Gyeongnam, 52828, Republic of Korea.,Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church St., Ann Arbor, MI, 48109, USA
| | - Gus R Rosania
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church St., Ann Arbor, MI, 48109, USA
| | - Meong Cheol Shin
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, 501 Jinju Daero, Jinju, Gyeongnam, 52828, Republic of Korea.
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15
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Min KA, Rosania GR, Kim CK, Shin MC. Functional and cytometric examination of different human lung epithelial cell types as drug transport barriers. Arch Pharm Res 2016; 39:359-69. [PMID: 26746641 DOI: 10.1007/s12272-015-0704-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/30/2015] [Indexed: 01/19/2023]
Abstract
To develop inhaled medications, various cell culture models have been used to examine the transcellular transport or cellular uptake properties of small molecules. For the reproducible high throughput screening of the inhaled drug candidates, a further verification of cell architectures as drug transport barriers can contribute to establishing appropriate in vitro cell models. In the present study, side-by-side experiments were performed to compare the structure and transport function of three lung epithelial cells (Calu-3, normal human bronchial primary cells (NHBE), and NL-20). The cells were cultured on the nucleopore membranes in the air-liquid interface (ALI) culture conditions, with cell culture medium in the basolateral side only, starting from day 1. In transport assays, paracellular transport across all three types of cells appeared to be markedly different with the NHBE or Calu-3 cells, showing low paracellular permeability and high TEER values, while the NL-20 cells showed high paracellular permeability and low TEER. Quantitative image analysis of the confocal microscope sections further confirmed that the Calu-3 cells formed intact cell monolayers in contrast to the NHBE and NL-20 cells with multilayers. Among three lung epithelial cell types, the Calu-3 cell cultures under the ALI condition showed optimal cytometric features for mimicking the biophysical characteristics of in vivo airway epithelium. Therefore, the Calu-3 cell monolayers could be used as functional cell barriers for the lung-targeted drug transport studies.
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Affiliation(s)
- Kyoung Ah Min
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, 501 Jinju Daero, Jinju, Gyeongnam, 52828, Republic of Korea.,Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church St., Ann Arbor, MI, 48109, USA
| | - Gus R Rosania
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church St., Ann Arbor, MI, 48109, USA
| | - Chong-Kook Kim
- College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Meong Cheol Shin
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, 501 Jinju Daero, Jinju, Gyeongnam, 52828, Republic of Korea.
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16
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Freishtat RJ, Nino G, Tsegaye Y, Alcala SE, Benton AS, Watson AM, Reeves EKM, Haider SK, Damsker JM. Pharmacologically-induced mitotic synchrony in airway epithelial cells as a mechanism of action of anti-inflammatory drugs. Respir Res 2015; 16:132. [PMID: 26511361 PMCID: PMC4625853 DOI: 10.1186/s12931-015-0293-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 09/25/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mitotic synchrony is the synchronous progression of a population of cells through the cell cycle and is characteristic of non-diseased airway epithelial cells. However, we previously showed that asthmatic airway epithelial cells are characterized by mitotic asynchrony and are pro-inflammatory as a result. Glucocorticoids can induce mitotic synchrony that in turn suppresses the pro-inflammatory state of diseased cells, suggesting a novel anti-inflammatory mechanism of action. Herein, we benchmarked traditional glucocorticoids against the ability of a new clinical-stage dissociative steroidal drug, VBP15, for mitotic resynchronization and associated anti-inflammatory activity in asthmatic airway epithelial cells. METHODS Primary airway epithelial cells differentiated at air-liquid interface were exposed to VBP15, dexamethasone or vehicle following in vitro mechanical injury. Basolateral cytokine secretions (TGF-β1, IL-6, IL-10, IL-13, and IL-1β) were analyzed at different time points using cytometric bead assays and mitosis was examined by flow cytometry. RESULTS VBP15 improved mitotic synchrony of proliferating asthmatic cells in air-liquid interface cultures compared to vehicle-exposed cultures. VBP15 also significantly reduced the basolateral secretion of pro-inflammatory (i.e. IL-1β) and pro-fibrogenic cytokines (i.e. TGF-β1) in air-liquid interface-differentiated asthmatic epithelial cultures following mechanical injury. CONCLUSION VBP15 improves mitotic asynchrony and injury-induced pro-inflammatory and fibrogenic responses in asthmatic airway epithelial cultures with efficacy comparable to traditional glucocorticoids. As it is predicted to show superior side effect profiles compared to traditional glucocorticoids, VBP15 holds potential for treatment of asthma and other respiratory conditions.
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Affiliation(s)
- R J Freishtat
- Division of Emergency Medicine, Children's National Health System, Washington, DC, USA. .,Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC, USA. .,Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
| | - G Nino
- Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC, USA. .,Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA. .,Division of Pulmonary and Sleep Medicine, Children's National Health System, Washington, DC, USA.
| | - Y Tsegaye
- George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
| | - S E Alcala
- George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
| | - A S Benton
- Children's National Health System, Washington, DC, USA.
| | - A M Watson
- George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
| | - E K M Reeves
- ReveraGen Biopharma, Inc., Silver Spring, MD, USA.
| | - S K Haider
- Division of Pulmonary and Sleep Medicine, Children's National Health System, Washington, DC, USA.
| | - J M Damsker
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA. .,ReveraGen Biopharma, Inc., Silver Spring, MD, USA.
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17
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Abstract
Asthma is characterized by chronic inflammation, airway hyperresponsiveness, and progressive airway remodeling. The airway epithelium is known to play a critical role in the initiation and perpetuation of these processes. Here, we review how excessive epithelial stress generated by bronchoconstriction is sufficient to induce airway remodeling, even in the absence of inflammatory cells.
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Affiliation(s)
- Jin-Ah Park
- Harvard T. H. Chan School of Public Health, Boston, Massachussetts
| | | | - Jeffrey M Drazen
- Harvard T. H. Chan School of Public Health, Boston, Massachussetts
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18
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Peters-Hall JR, Brown KJ, Pillai DK, Tomney A, Garvin LM, Wu X, Rose MC. Quantitative proteomics reveals an altered cystic fibrosis in vitro bronchial epithelial secretome. Am J Respir Cell Mol Biol 2015; 53:22-32. [PMID: 25692303 PMCID: PMC4566109 DOI: 10.1165/rcmb.2014-0256rc] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 02/05/2015] [Indexed: 12/25/2022] Open
Abstract
Alterations in epithelial secretions and mucociliary clearance contribute to chronic bacterial infection in cystic fibrosis (CF) lung disease, but whether CF lungs are unchanged in the absence of infection remains controversial. A proteomic comparison of airway secretions from subjects with CF and control subjects shows alterations in key biological processes, including immune response and proteolytic activity, but it is unclear if these are due to mutant CF transmembrane conductance regulator (CFTR) and/or chronic infection. We hypothesized that the CF lung apical secretome is altered under constitutive conditions in the absence of inflammatory cells and pathogens. To test this, we performed quantitative proteomics of in vitro apical secretions from air-liquid interface cultures of three life-extended CF (ΔF508/ΔF508) and three non-CF human bronchial epithelial cells after labeling of CF cells by stable isotope labeling with amino acids in cell culture. Mass spectrometry analysis identified and quantitated 666 proteins across samples, of which 70 exhibited differential enrichment or depletion in CF secretions (±1.5-fold change; P < 0.05). The key molecular functions were innate immunity (24%), cytoskeleton/extracellular matrix organization (24%), and protease/antiprotease activity (17%). Oxidative proteins and classical complement pathway proteins that are altered in CF secretions in vivo were not altered in vitro. Specific differentially increased proteins-MUC5AC and MUC5B mucins, fibronectin, and matrix metalloproteinase-9-were validated by antibody-based assays. Overall, the in vitro CF secretome data are indicative of a constitutive airway epithelium with altered innate immunity, suggesting that downstream consequences of mutant CFTR set the stage for chronic inflammation and infection in CF airways.
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Affiliation(s)
| | - Kristy J. Brown
- Departments of Integrative Systems Biology and
- Pediatrics, George Washington University School of Medicine, Washington, DC; and
- Research Center for Genetic Medicine and
| | - Dinesh K. Pillai
- Departments of Integrative Systems Biology and
- Pediatrics, George Washington University School of Medicine, Washington, DC; and
- Research Center for Genetic Medicine and
- Division of Pulmonary and Sleep Medicine, Children's National, Washington, DC
| | | | - Lindsay M. Garvin
- Departments of Integrative Systems Biology and
- Research Center for Genetic Medicine and
| | - Xiaofang Wu
- Departments of Integrative Systems Biology and
- Pediatrics, George Washington University School of Medicine, Washington, DC; and
- Research Center for Genetic Medicine and
| | - Mary C. Rose
- Departments of Integrative Systems Biology and
- Pediatrics, George Washington University School of Medicine, Washington, DC; and
- Research Center for Genetic Medicine and
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19
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Wu X, Mimms R, Banigan M, Lee M, Elkis V, Peters-Hall JR, Mubeen H, Joselow A, Peña MT, Rose MC. Development of glandular models from human nasal progenitor cells. Am J Respir Cell Mol Biol 2015; 52:535-42. [PMID: 25412193 PMCID: PMC4491133 DOI: 10.1165/rcmb.2013-0259ma] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 11/12/2014] [Indexed: 11/24/2022] Open
Abstract
Hyperplasia/hypertrophy of submucosal glands contributes to mucus overproduction in chronic diseases of the upper and lower respiratory tracts, especially in adult and pediatric chronic rhinosinusitis. Mechanisms that lead to glandular hyperplasia/hypertrophy are markedly understudied, reflecting a lack of in vitro model systems wherein airway epithelial progenitor cells differentiate into glandular cells. In this study, we developed and compared several in vitro three-dimensional systems using human nasal epithelial basal cells (HNEBCs) cultured by different methods on two types of extracellular matrices. We demonstrate that HNEBCs cultured on Matrigel (Corning, Tewksbury, MA) form glandular acini-like structures, whereas HNEBCs embedded in a collagen type I matrix form a network of tubules. Fibroblast-conditioned medium increases tubule formation in collagen type I. In contrast, HNEBCs cocultured with fibroblasts self-aggregate into organotypic structures with tubules and acini. These observations provide morphological evidence that HNEBCs are pluripotent and retain the capacity to differentiate into structures resembling specific structural components of submucosal glands depending on the extracellular matrices and culture conditions. The resultant models should prove useful in targeting cross-talk between epithelial cells and fibroblasts to decipher molecular mechanisms and specific signals responsible for the development of glandular hyperplasia/hypertrophy, which in turn may lead to new therapeutic strategies for chronic rhinosinusitis and other inflammatory respiratory diseases characterized by glandular hyperplasia/hypertrophy.
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Affiliation(s)
- Xiaofang Wu
- Center for Genetic Medicine Research and
- Departments of Integrative Systems Biology
- Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, D.C
| | - Remy Mimms
- Center for Genetic Medicine Research and
| | | | | | | | | | | | | | - Maria T. Peña
- Center for Genetic Medicine Research and
- Division of Otolaryngology, Children’s National Medical Center, Washington, D.C.; and
- Otolaryngology, and
- Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, D.C
| | - Mary C. Rose
- Center for Genetic Medicine Research and
- Departments of Integrative Systems Biology
- Biochemistry and Molecular Medicine
- Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, D.C
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20
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Van de Laar E, Clifford M, Hasenoeder S, Kim BR, Wang D, Lee S, Paterson J, Vu NM, Waddell TK, Keshavjee S, Tsao MS, Ailles L, Moghal N. Cell surface marker profiling of human tracheal basal cells reveals distinct subpopulations, identifies MST1/MSP as a mitogenic signal, and identifies new biomarkers for lung squamous cell carcinomas. Respir Res 2014; 15:160. [PMID: 25551685 PMCID: PMC4343068 DOI: 10.1186/s12931-014-0160-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 12/17/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The large airways of the lungs (trachea and bronchi) are lined with a pseudostratified mucociliary epithelium, which is maintained by stem cells/progenitors within the basal cell compartment. Alterations in basal cell behavior can contribute to large airway diseases including squamous cell carcinomas (SQCCs). Basal cells have traditionally been thought of as a uniform population defined by basolateral position, cuboidal cell shape, and expression of pan-basal cell lineage markers like KRT5 and TP63. While some evidence suggests that basal cells are not all functionally equivalent, few heterogeneously expressed markers have been identified to purify and study subpopulations. In addition, few signaling pathways have been identified that regulate their cell behavior. The goals of this work were to investigate tracheal basal cell diversity and to identify new signaling pathways that regulate basal cell behavior. METHODS We used flow cytometry (FACS) to profile cell surface marker expression at a single cell level in primary human tracheal basal cell cultures that maintain stem cell/progenitor activity. FACS results were validated with tissue staining, in silico comparisons with normal basal cell and lung cancer datasets, and an in vitro proliferation assay. RESULTS We identified 105 surface markers, with 47 markers identifying potential subpopulations. These subpopulations generally fell into more (~ > 13%) or less abundant (~ < 6%) groups. Microarray gene expression profiling supported the heterogeneous expression of these markers in the total population, and immunostaining of large airway tissue suggested that some of these markers are relevant in vivo. 24 markers were enriched in lung SQCCs relative to adenocarcinomas, with four markers having prognostic significance in SQCCs. We also identified 33 signaling receptors, including the MST1R/RON growth factor receptor, whose ligand MST1/MSP was mitogenic for basal cells. CONCLUSION This work provides the largest description to date of molecular diversity among human large airway basal cells. Furthermore, these markers can be used to further study basal cell function in repair and disease, and may aid in the classification and study of SQCCs.
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Affiliation(s)
- Emily Van de Laar
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Monica Clifford
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Stefan Hasenoeder
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
- />Present address: Helmholtz Zentrum München, Institute of Stem Cell Research, Ingolstädter Landstrasse 1, 85746 Neuherberg, Germany
| | - Bo Ram Kim
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Dennis Wang
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Sharon Lee
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
- />Department of Applied Mathematics, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1 Canada
| | - Josh Paterson
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Nancy M Vu
- />Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112 USA
- />Present address: University of Utah School of Medicine, Salt Lake City, UT 84132 USA
| | - Thomas K Waddell
- />Toronto Lung Transplant Program, University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Shaf Keshavjee
- />Toronto Lung Transplant Program, University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Ming-Sound Tsao
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Laurie Ailles
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
| | - Nadeem Moghal
- />Department of Medical Biophysics, Ontario Cancer Institute/Campbell Family Cancer Research Institute/Princess Margaret Cancer Centre/University Health Network, University of Toronto, Toronto, ON M5G 1 L7 Canada
- />Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112 USA
- />Present address: Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON M5G 1 L7 Canada
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21
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Zhu L, Lee B, Zhao F, Zhou X, Chin V, Ling SC, Chen Y. Modulation of airway epithelial antiviral immunity by fungal exposure. Am J Respir Cell Mol Biol 2014; 50:1136-43. [PMID: 24428709 DOI: 10.1165/rcmb.2013-0357oc] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Multiple pathogens, such as bacteria, fungi, and viruses, have been frequently found in asthmatic airways and are associated with the pathogenesis and exacerbation of asthma. Among these pathogens, Alternaria alternata (Alt), a universally present fungus, and human rhinovirus have been extensively studied. However, their interactions have not been investigated. In the present study, we tested the effect of Alt exposure on virus-induced airway epithelial immunity using live virus and a synthetic viral mimicker, double-stranded RNA (dsRNA). Alt treatment was found to significantly enhance the production of proinflammatory cytokines (e.g., IL-6 and IL-8) induced by virus infection or dsRNA treatment. In contrast to this synergistic effect, Alt significantly repressed type I and type III IFN production, and this impairment led to elevated viral replication. Mechanistic studies suggested the positive role of NF-κB and mitogen-activated protein kinase pathways in the synergism and the attenuation of the TBK1-IRF3 pathway in the inhibition of IFN production. These opposite effects are caused by separate fungal components. Protease-dependent and -independent mechanisms appear to be involved. Thus, Alt exposure alters the airway epithelial immunity to viral infection by shifting toward more inflammatory but less antiviral responses.
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Affiliation(s)
- Lingxiang Zhu
- 1 Department of Pharmacology and Toxicology, School of Pharmacy, University of Arizona, Tucson, Arizona; and
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22
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Carrier interactions with the biological barriers of the lung: advanced in vitro models and challenges for pulmonary drug delivery. Adv Drug Deliv Rev 2014; 75:129-40. [PMID: 24880145 DOI: 10.1016/j.addr.2014.05.014] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 05/15/2014] [Accepted: 05/23/2014] [Indexed: 11/22/2022]
Abstract
In recent years significant progress has been made to improve particle deposition in the lung. However, the development of strategies to overcome the air-blood lung barrier is still needed. The combination of complex in vitro models and sophisticated particulate carriers is promising as a strategy by which that goal could be achieved. In this review we discuss currently available in vitro lung models, including some recent tissue-engineering approaches, as well as the challenges associated to implement such complex in vitro systems. Furthermore, we discuss available carrier technologies, often based on nanotechnology, to target specific regions of the lungs and to overcome the respective biological barriers, ideally resulting in safe and effective delivery to the desired pulmonary destination.
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23
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Hou HH, Cheng SL, Chung KP, Kuo MYP, Yeh CC, Chang BE, Lu HH, Wang HC, Yu CJ. Elastase induces lung epithelial cell autophagy through placental growth factor: a new insight of emphysema pathogenesis. Autophagy 2014; 10:1509-21. [PMID: 24988221 DOI: 10.4161/auto.29190] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a devastating disease, which is associated with increasing mortality and morbidity. Therefore, there is a need to clearly define the COPD pathogenic mechanism and to explore effective therapies. Previous studies indicated that cigarette smoke (CS) induces autophagy and apoptosis in lung epithelial (LE) cells. Excessive ELANE/HNE (elastase, neutrophil elastase), a factor involved in protease-antiprotease imbalance and the pathogenesis of COPD, causes LE cell apoptosis and upregulates the expression of several stimulus-responsive genes. However, whether or not elastase induces autophagy in LE cell remains unknown. The level of PGF (placental growth factor) is higher in COPD patients than non-COPD controls. We hypothesize that elastase induces PGF expression and causes autophagy in LE cells. In this study, we demonstrated that porcine pancreatic elastase (PPE) induced PGF expression and secretion in LE cells in vitro and in vivo. The activation of MAPK8/JNK1 (mitogen-activated protein kinase 8) and MAPK14/p38alpha MAPK signaling pathways was involved in the PGF mediated regulation of the TSC (tuberous sclerosis complex) pathway and autophagy in LE cells. Notably, PGF-induced MAPK8 and MAPK14 signaling pathways mediated the inactivation of MTOR (mechanistic target of rapamycin), the upregulation of MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 β) and the increase of autophagosome formation in mice. Furthermore, the PPE-induced autophagy promotes further apoptosis in vitro and in vivo. In summary, elastase-induced autophagy promotes LE cell apoptosis and pulmonary emphysema through the upregulation of PGF. PGF and its downstream MAPK8 and MAPK14 signaling pathways are potential therapeutic targets for the treatment of emphysema and COPD.
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Affiliation(s)
- Hsin-Han Hou
- Department of Internal Medicine; National Taiwan University Hospital; Taiwan; Department of Internal Medicine; College of Medicine; National Taiwan University; Taiwan
| | - Shih-Lung Cheng
- Department of Internal Medicine; Far Eastern Memorial Hospital; Taiwan; Department of Chemical Engineering and Materials Science; Yuan-Ze University; Taiwan
| | - Kuei-Pin Chung
- Department of Laboratory Medicine; National Taiwan University Hospital; Taiwan
| | - Mark Yen-Ping Kuo
- Graduate Institute of Clinical Dentistry; School of Dentistry; National Taiwan University; Taiwan; Department of Dentistry; National Taiwan University Hospital; National Taiwan University; Taiwan
| | - Cheng-Chang Yeh
- Graduate Institute of Clinical Dentistry; School of Dentistry; National Taiwan University; Taiwan; Department of Dentistry; National Taiwan University Hospital; National Taiwan University; Taiwan
| | - Bei-En Chang
- Graduate Institute of Oral Biology; School of Dentistry; National Taiwan University; Taiwan
| | - Hsuan-Hsuan Lu
- Department of Internal Medicine; National Taiwan University Hospital; Taiwan; Department of Internal Medicine; College of Medicine; National Taiwan University; Taiwan
| | - Hao-Chien Wang
- Department of Internal Medicine; National Taiwan University Hospital; Taiwan; Department of Internal Medicine; College of Medicine; National Taiwan University; Taiwan
| | - Chong-Jen Yu
- Department of Internal Medicine; National Taiwan University Hospital; Taiwan; Department of Internal Medicine; College of Medicine; National Taiwan University; Taiwan
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24
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Chen Y, Garvin LM, Nickola TJ, Watson AM, Colberg-Poley AM, Rose MC. IL-1β induction of MUC5AC gene expression is mediated by CREB and NF-κB and repressed by dexamethasone. Am J Physiol Lung Cell Mol Physiol 2014; 306:L797-807. [PMID: 24487386 PMCID: PMC3989721 DOI: 10.1152/ajplung.00347.2013] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/29/2014] [Indexed: 12/17/2022] Open
Abstract
Chronic airway diseases are characterized by inflammation and mucus overproduction. The MUC5AC mucin gene is upregulated by the proinflammatory cytokine interleukin-1 β (IL-1β) via activation of cAMP response element-binding protein (CREB) in the NCI-H292 cancer cell line and nuclear factor-κB (NF-κB) in the HBE1 transformed cell line, with each transcription factor binding to a cognate cis site in the proximal or distal region, respectively, of the MUC5AC promoter. We utilized primary differentiated human bronchial epithelial (HBE) and A549 lung adenocarcinoma cells to further investigate the contributions of CREB and NF-κB subunits to the IL-1β-induced upregulation of MUC5AC. Data show that ligand binding of IL-1β to the IL-1β receptor is required to increase MUC5AC mRNA abundance. Chromatin immunoprecipitation analyses show direct binding of CREB to the previously identified cAMP response element site and binding of p65 and p50 subunits to a novel NF-κB site in a mucin-regulatory domain in the proximal promoter and to a previously identified NF-κB site in the distal promoter. P50 binds to both NF-κB sites at 1 h following IL-1β exposure, but is replaced at 2 h by p65 in A549 cells and by a p50/p65 heterodimer in HBE cells. Thus IL-1β activates multiple domains in the MUC5AC promoter but exhibits some cell-specific responses, highlighting the complexity of MUC5AC transcriptional regulation. Data show that dexamethasone, a glucocorticoid that transcriptionally represses MUC5AC gene expression under constitutive conditions, also represses IL-1β-mediated upregulation of MUC5AC gene expression. A further understanding of mechanisms mediating MUC5AC regulation should lead to a honing of therapeutic approaches for the treatment of mucus overproduction in inflammatory lung diseases.
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Affiliation(s)
- Yajun Chen
- Children's National, 111 Michigan Ave NW, Washington, DC 20010.
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25
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Hoffman SM, Tully JE, Nolin JD, Lahue KG, Goldman DH, Daphtary N, Aliyeva M, Irvin CG, Dixon AE, Poynter ME, Anathy V. Endoplasmic reticulum stress mediates house dust mite-induced airway epithelial apoptosis and fibrosis. Respir Res 2013; 14:141. [PMID: 24364984 PMCID: PMC3877992 DOI: 10.1186/1465-9921-14-141] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 12/17/2013] [Indexed: 12/26/2022] Open
Abstract
Background The endoplasmic reticulum (ER) stress response participates in many chronic inflammatory and autoimmune diseases. In the current study, we sought to examine the contribution of ER stress transducers in the pathogenesis of three principal facets of allergic asthma: inflammation, airway fibrosis, and airways hyperresponsiveness. Methods House Dust Mite (HDM) was used as an allergen for in vitro and in vivo challenge of primary human and murine airway epithelial cells. ER stress transducers were modulated using specific small interfering RNAs (siRNAs) in vivo. Inflammation, airway remodeling, and hyperresponsiveness were measured by total bronchoalveolar lavage (BAL) cell counts, determination of collagen, and methacholine responsiveness in mice, respectively. Results Challenge of human bronchiolar and nasal epithelial cells with HDM extract induced the ER stress transducer, activating transcription factor 6 α (ATF6α) as well as protein disulfide isomerase, ERp57, in association with activation of caspase-3. SiRNA-mediated knockdown of ATF6α and ERp57 during HDM administration in mice resulted in a decrease in components of HDM-induced ER stress, disulfide mediated oligomerization of Bak, and activation of caspase-3. Furthermore, siRNA-mediated knockdown of ATF6α and ERp57 led to decreased inflammation, airway hyperresponsiveness and airway fibrosis. Conclusion Collectively, our work indicates that HDM induces ER stress in airway epithelial cells and that ATF6α and ERp57 play a significant role in the development of cardinal features of allergic airways disease. Inhibition of ER stress responses may provide a potential therapeutic avenue in chronic asthma and sub-epithelial fibrosis associated with loss of lung function.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Vikas Anathy
- Department of Pathology, Vermont Lung Center University of Vermont College of Medicine, Burlington, VT 05405, USA.
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Tully JE, Hoffman SM, Lahue KG, Nolin JD, Anathy V, Lundblad LKA, Daphtary N, Aliyeva M, Black KE, Dixon AE, Poynter ME, Irvin CG, Janssen-Heininger YMW. Epithelial NF-κB orchestrates house dust mite-induced airway inflammation, hyperresponsiveness, and fibrotic remodeling. THE JOURNAL OF IMMUNOLOGY 2013; 191:5811-21. [PMID: 24227776 DOI: 10.4049/jimmunol.1301329] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
NF-κB activation within the epithelium has been implicated in the pathogenesis of asthma, yet the exact role of epithelial NF-κB in allergen-induced inflammation and airway remodeling remains unclear. In the current study, we used an intranasal house dust mite (HDM) extract exposure regimen time course in BALB/c mice to evaluate inflammation, NF-κB activation, airway hyperresponsiveness (AHR), and airway remodeling. We used CC10-IκBαSR transgenic mice to evaluate the functional importance of epithelial NF-κB in response to HDM. After a single exposure of HDM, mRNA expression of proinflammatory mediators was significantly elevated in lung tissue of wild-type (WT) mice, in association with increases in nuclear RelA and RelB, components of the classical and alternative NF-κB pathway, respectively, in the bronchiolar epithelium. In contrast, CC10-IκBαSR mice displayed marked decreases in nuclear RelA and RelB and mRNA expression of proinflammatory mediators compared with WT mice. After 15 challenges with HDM, WT mice exhibited increases in inflammation, AHR, mucus metaplasia, and peribronchiolar fibrosis. CC10-IκBαSR transgenic mice displayed marked decreases in neutrophilic infiltration, tissue damping, and elastance parameters, in association will less peribronchiolar fibrosis and decreases in nuclear RelB in lung tissue. However, central airway resistance and mucus metaplasia remained elevated in CC10-IκBαSR transgenic mice, in association with the continued presence of lymphocytes, and partial decreases in eosinophils and IL-13. The current study demonstrates that following airway exposure with an asthma-relevant allergen, activation of classical and alternative NF-κB pathways occurs within the airway epithelium and may coordinately contribute to allergic inflammation, AHR, and fibrotic airway remodeling.
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Affiliation(s)
- Jane E Tully
- Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405
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Horani A, Nath A, Wasserman MG, Huang T, Brody SL. Rho-associated protein kinase inhibition enhances airway epithelial Basal-cell proliferation and lentivirus transduction. Am J Respir Cell Mol Biol 2013; 49:341-7. [PMID: 23713995 DOI: 10.1165/rcmb.2013-0046te] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The identification of factors that regulate airway epithelial cell proliferation and differentiation are essential for understanding the pathophysiology of airway diseases. Rho-associated protein kinases (ROCKs) are downstream effector proteins of RhoA GTPase that direct the functions of cell cytoskeletal proteins. ROCK inhibition with Y27632 has been shown to enhance the survival and cloning of human embryonic stem cells and pluripotent cells in other tissues. We hypothesized that Y27632 treatment exerts a similar effect on airway epithelial basal cells, which function as airway epithelial progenitor cells. Treatment with Y27632 enhanced basal-cell proliferation in cultured human tracheobronchial and mouse tracheal epithelial cells. ROCK inhibition accelerated the maturation of basal cells, characterized by a diminution of the cell size associated with cell compaction and the expression of E-cadherin at cell-cell junctions. Transient treatment of cultured basal cells with Y27632 did not affect subsequent ciliated or mucous cell differentiation under air-liquid interface conditions, and allowed for the initial use of lower numbers of human or mouse primary airway epithelial cells than otherwise possible. Moreover, the use of Y27632 during lentivirus-mediated transduction significantly improved posttransduction efficiency and the selection of a transduced cell population, as determined by reporter gene expression. These findings suggest an important role for ROCKs in the regulation of proliferation and maturation of epithelial basal cells, and demonstrate that the inhibition of ROCK pathways using Y27632 provides an adjunctive tool for the in vitro genetic manipulation of airway epithelial cells by lentivirus vectors.
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Affiliation(s)
- Amjad Horani
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
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Epithelial cell culture from human adenoids: a functional study model for ciliated and secretory cells. BIOMED RESEARCH INTERNATIONAL 2013; 2013:478713. [PMID: 23484122 PMCID: PMC3581098 DOI: 10.1155/2013/478713] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 11/16/2012] [Accepted: 11/19/2012] [Indexed: 11/23/2022]
Abstract
Background. Mucociliary transport (MCT) is a defense mechanism of the airway. To study the underlying mechanisms of MCT, we have both developed an experimental model of cultures, from human adenoid tissue of ciliated and secretory cells, and characterized the response to local chemical signals that control ciliary activity and the secretion of respiratory mucins in vitro. Materials and Methods. In ciliated cell cultures, ciliary beat frequency (CBF) and intracellular Ca2+ levels were measured in response to ATP, UTP, and adenosine. In secretory cultures, mucin synthesis and secretion were identified by using immunodetection. Mucin content was taken from conditioned medium and analyzed in the presence or absence of UTP. Results. Enriched ciliated cell monolayers and secretory cells were obtained. Ciliated cells showed a basal CBF of 10.7 Hz that increased significantly after exposure to ATP, UTP, or adenosine. Mature secretory cells showed active secretion of granules containing different glycoproteins, including MUC5AC. Conclusion. Culture of ciliated and secretory cells grown from adenoid epithelium is a reproducible and feasible experimental model, in which it is possible to observe ciliary and secretory activities, with a potential use as a model to understand mucociliary transport control mechanisms.
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Chen Y, Watson AM, Williamson CD, Rahimi M, Liang C, Colberg-Poley AM, Rose MC. Glucocorticoid receptor and histone deacetylase-2 mediate dexamethasone-induced repression of MUC5AC gene expression. Am J Respir Cell Mol Biol 2012; 47:637-44. [PMID: 22798432 PMCID: PMC3547101 DOI: 10.1165/rcmb.2012-0009oc] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 07/09/2012] [Indexed: 01/05/2023] Open
Abstract
Airway occlusion in obstructive airway diseases is caused in part by the overproduction of secretory mucin glycoproteins through the up-regulation of mucin (MUC) genes by inflammatory mediators. Some pharmacological agents, including the glucocorticoid dexamethasone (Dex), repress mucin concentrations in lung epithelial cancer cells. Here, we show that Dex reduces the expression of MUC5AC, a major airway mucin gene, in primary differentiated normal human bronchial epithelial (NHBE) cells in a dose-dependent and time-dependent manner, and that the Dex-induced repression is mediated by the glucocorticoid receptor (GR) and two glucocorticoid response elements (GREs) in the MUC5AC promoter. The pre-exposure of cells to RU486, a GR antagonist, and mutations in either the GRE3 or GRE5 cis-sites abolished the Dex-induced repression. Chromatin immunoprecipitation (ChIP) assays showed a rapid temporal recruitment of GR to the GRE3 and GRE5 cis-elements in the MUC5AC promoter in NHBE and in A549 cells. Immunofluorescence showed nuclear colocalization of GR and histone deacetylase-2 (HDAC2) in MUC5AC-expressing NHBE cells. ChIP also showed a rapid temporal recruitment of HDAC2 to the GRE3 and GRE5 cis-elements in the MUC5AC promoter in both cell types. The knockdown of HDAC2 by HDAC2-specific short interfering RNA prevented the Dex-induced repression of MUC5AC in NHBE and A549 cells. These data demonstrate that GR and HDAC2 are recruited to the GRE3 and GRE5 cis-sites in the MUC5AC promoter and mediate the Dex-induced cis repression of MUC5AC gene expression. A better understanding of the mechanisms whereby glucocorticoids repress MUC5AC gene expression may be useful in formulating therapeutic interventions in chronic lung diseases.
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Affiliation(s)
- Yajun Chen
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC; and
| | - Alan M. Watson
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC; and
| | | | - Michael Rahimi
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC; and
| | - Chong Liang
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC; and
| | - Anamaris M. Colberg-Poley
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC; and
- Department of Biochemistry and Molecular Biology
- Department of Integrative Systems Biology, and
- Department of Pediatrics, George Washington University, Washington, DC
| | - Mary C. Rose
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC; and
- Department of Biochemistry and Molecular Biology
- Department of Integrative Systems Biology, and
- Department of Pediatrics, George Washington University, Washington, DC
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Combination erlotinib-cisplatin and Atg3-mediated autophagy in erlotinib resistant lung cancer. PLoS One 2012; 7:e48532. [PMID: 23119048 PMCID: PMC3485310 DOI: 10.1371/journal.pone.0048532] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 09/27/2012] [Indexed: 01/23/2023] Open
Abstract
Tyrosine kinase inhibitors such as erlotinib are commonly used as a therapeutic agent against cancer due to its relatively low side-effect profile and, at times, greater efficacy. However, erlotinib resistance (ER) in non-small cell lung cancer is being recognized as a major problem. Therefore, understanding the mechanism behind ER and developing effective regimens are needed. Autophagy’s role in cancer has been controversial and remains unclear. In this study, we examined the effectiveness of low dose erlotinib-cisplatin combination in erlotinib resistant lung adenocarcinoma (ERPC9) cells and the role of autophagy in ER. ERPC9 cells were established from erlotinib sensitive PC9 cells. Appropriate treatments were done over two days and cell survival was quantified with Alamar Blue assay. LC3II and regulatory proteins of autophagy were measured by western blot. Small interfering RNA (siRNA) was utilized to inhibit translation of the protein of interest. In ERPC9 cells, combination treatment induced synergistic cell death and a significant decrease in autophagy. At baseline, ERPC9 cells had a significantly higher LC3II and lower p-mTOR levels compared to PC9 cells. The addition of rapamycin increased resistance and 3-methyladenine sensitized ERPC9 cells, indicating autophagy may be acting as a protective mechanism. Further examination revealed that ERPC9 cells harbored high baseline Atg3 levels. The high basal Atg3 was targeted and significantly lowered with combination treatment. siRNA transfection of Atg3 resulted in the reversal of ER; 42.0% more cells died in erlotinib-alone treatment with transfection compared to non-transfected ERPC9 cells. We reveal a novel role for Atg3 in the promotion of ER as the inhibition of Atg3 translation was able to result in the re-sensitization of ERPC9 cells to erlotinib-alone treatment. Also, we demonstrate that combination erlotinib-cisplatin is an effective treatment against erlotinib resistant cancer by targeting (down-regulating) Atg3 mediated autophagy and induction of apoptotic cell death.
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Bateman AC, Karasin AI, Olsen CW. Differentiated swine airway epithelial cell cultures for the investigation of influenza A virus infection and replication. Influenza Other Respir Viruses 2012; 7:139-50. [PMID: 22530566 PMCID: PMC3443301 DOI: 10.1111/j.1750-2659.2012.00371.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Please cite this paper as: Bateman et al. (2013) Differentiated swine airway epithelial cell cultures for the investigation of influenza A virus infection and replication. Influenza and Other Respiratory Viruses 7(2) 139–150. Background Differentiated human airway epithelial cell cultures have been utilized to investigate cystic fibrosis, wound healing, and characteristics of viral infections. These cultures, grown at an air–liquid interface (ALI) in media with defined hormones and growth factors, recapitulate many aspects of the in vivo respiratory tract and allow for experimental studies at the cellular level. Objectives To optimize growth conditions for differentiated swine airway epithelial cultures and to use these cultures to examine influenza virus infection and replication. Methods Primary swine respiratory epithelial cells were grown at an air–liquid interface with varying amounts of retinoic acid and epidermal growth factor. Cells grown with optimized concentrations of these factors for 4 weeks differentiated into multilayer epithelial cell cultures resembling the lining of the swine respiratory tract. Influenza virus infection and replication were examined in these cultures. Results/Conclusions Retinoic acid promoted ciliogenesis, whereas epidermal growth factor controlled the thickness of the pseudoepithelium. The optimal concentrations for differentiated swine cell cultures were 1·5 ng/ml epidermal growth factor and 100 nm retinoic acid. Influenza A viruses infected and productively replicated in these cultures in the absence of exogenous trypsin, suggesting that the cultures express a protease capable of activating influenza virus hemagglutinin. Differences in virus infection and replication characteristics found previously in pigs in vivo were recapitulated in the swine cultures. This system could be a useful tool for a range of applications, including investigating influenza virus species specificity, defining cell tropism of influenza viruses in the swine respiratory epithelium, and studying other swine respiratory diseases.
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Affiliation(s)
- Allen C Bateman
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
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Swindle EJ, Davies DE. Artificial airways for the study of respiratory disease. Expert Rev Respir Med 2012; 5:757-65. [PMID: 22082162 DOI: 10.1586/ers.11.78] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This review will focus on human cell-based experimental models to study respiratory diseases, in particular models of the large airways relevant to asthma and chronic obstructive pulmonary disease. Such models have the advantage of incorporating cells that can be derived from disease-relevant tissue and so have retained important genetic and epigenetic features that contribute to the human disease. These models can be used for mechanistic studies, target identification and validation and toxicological testing. While many models have been developed to varying degrees of sophistication, the challenge remains to develop an integrated system that recapitulates the complex cell-cell and cell-matrix interactions that occur in vivo and to provide these with a 'circulation' to study the dynamics of immune and inflammatory cell influx and efflux.
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Affiliation(s)
- Emily J Swindle
- Academic Unit of Clinical and Experimental Sciences and Southampton NIHR Respiratory Biomedical Research Unit, Sir Henry Wellcome Laboratories, University of Southampton Faculty of Medicine, Southampton General Hospital, Southampton, SO16 6YD, UK.
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Tao S, Zhu L, Lee P, Lee WM, Knox K, Chen J, Di YP, Chen Y. Negative control of TLR3 signaling by TICAM1 down-regulation. Am J Respir Cell Mol Biol 2011; 46:660-7. [PMID: 22205631 DOI: 10.1165/rcmb.2011-0340oc] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Toll-IL-1 receptor (TIR) domain-containing adaptor molecule-1 (TICAM1, also called TRIF) is an important adaptor protein in TLR3 and TLR4 signaling pathways that mediate proinflammatory cytokine and IFN responses. Negative regulation of TICAM1 by exogenous viral protease or by endogenous caspase and proteasome have been reported to shut down TICAM1-mediated signaling. In this study, we discovered that down-regulation of TICAM1, but not other components in this signaling pathway, occurred in a natural process of TLR3 activation induced by double-stranded RNA or human rhinovirus (RV) infection in airway epithelial cells and various other cell types. TICAM1 was essential for IFN expression, and the loss of TICAM1 significantly elevated RV production. The low level of TICAM1 protein expression, caused by the prior double-stranded RNA treatment, led to a lack of IFN production upon additional treatment, suggesting receptor desensitization. In follow-up studies, TICAM1 down-regulation was found to be dependent on TLR3 but not RIG1, MDA5, or PKR and appeared to be regulated post-translationally. Neither proteasome nor caspase inhibitors could prevent TICAM1 down-regulation. Instead, a lysosome-mediated process appeared to be involved, suggesting a novel mechanism that is different from previous reports. In conclusion, TICAM1 down-regulation is an essential step in TLR3 activation, and its function is to stop TLR3-mediated IFN production.
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Affiliation(s)
- Shasha Tao
- School of Public Health, China Medical University, Shenyang, China
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Zhang XH, Zhang YN, Li HB, Hu CY, Wang N, Cao PP, Liao B, Lu X, Cui YH, Liu Z. Overexpression of miR-125b, a novel regulator of innate immunity, in eosinophilic chronic rhinosinusitis with nasal polyps. Am J Respir Crit Care Med 2011; 185:140-51. [PMID: 22071331 DOI: 10.1164/rccm.201103-0456oc] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
RATIONALE Eosinophilic chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) represents a hard-to-treat subtype of CRS. OBJECTIVES To determine the pattern of expression and biologic role of microRNAs (miRNAs) in CRS, particularly in eosinophilic CRSwNP. METHODS Global miRNA expression in sinonasal mucosa from controls, CRS without nasal polyps (CRSsNP), and patients with eosinophilic CRSwNP was compared using miRNA microarrays. MiR-125b expression was detected by means of quantitative reverse-transcriptase polymerase chain reaction. The cellular localization of miR-125b was determined by in situ hybridization. MiR-125b functional assays were performed on airway epithelial cells and mice. MiR-125b expression regulation was studied by tissue and cell culture. MEASUREMENTS AND MAIN RESULTS CRSsNP and eosinophilic CRSwNP exhibited distinct miRNA expression profiles. MiR-125b was specifically up-regulated in eosinophilic CRSwNP. MiR-125b was mainly expressed by sinonasal and bronchial epithelial cells. EIF4E-binding protein 1 (4E-BP1) was identified as a direct target of miR-125b. MiR-125b mimic or inhibitor enhanced or decreased IFN-α/β production elicited by dsRNA in vitro or in vivo, respectively. 4E-BP1 expression was decreased, whereas IFN regulatory factor-7 and IFN-β expression was increased, in eosinophilic CRSwNP. IFN-β mRNA levels positively correlated with IL-5 mRNA levels and eosinophil infiltration in sinonasal mucosa. IFN-β stimulated B cell-activating factor of the tumor necrosis factor family production in airway epithelial cells. miR-125b could be induced by lipopolysaccharide, dsRNA, and IL-10. CONCLUSIONS The up-regulated expression of miR-125b may enhance type I IFN expression through suppressing 4E-BP1 protein expression in airway epithelial cells, which potentially contributes to mucosal eosinophilia in eosinophilic CRSwNP.
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Affiliation(s)
- Xin-Hao Zhang
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, PR China
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Koning H, Sayers I, Stewart CE, de Jong D, Ten Hacken NHT, Postma DS, van Oosterhout AJM, Nawijn MC, Koppelman GH. Characterization of protocadherin-1 expression in primary bronchial epithelial cells: association with epithelial cell differentiation. FASEB J 2011; 26:439-48. [PMID: 21982948 DOI: 10.1096/fj.11-185207] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Protocadherin-1 (PCDH1) is a novel susceptibility gene for asthma that is expressed in airway epithelium. We aimed to characterize PCDH1 mRNA transcripts and protein expression in primary bronchial epithelial cells and to determine regulation of PCDH1 during mucociliary differentiation. Total RNA and protein were isolated from human primary bronchial epithelial cells. PCDH1 transcripts were characterized by rapid amplification of cDNA ends in bronchial epithelial cells of 4 subjects. PCDH1 expression was quantified by quantitative RT-PCR and Western blotting in bronchial epithelial cells directly ex vivo and after air liquid interface (ALI) or submerged culture. We identified 5 novel exons on the 5' end and 1 exon on the 3' end of PCDH1. Novel transcripts showed major variation in expression of intracellular conserved motifs. Expression levels of PCDH1 transcripts encoding exon 1-2 were 4-fold higher, and transcripts encoding exon 3-4 were 15-fold higher in freshly isolated bronchial epithelial cells than in submerged cultures. PCDH1 mRNA (3- to 8-fold) and protein levels (2- to 3-fold) were strongly up-regulated during mucociliary differentiation of primary bronchial epithelial cells in ALI cultures. In summary, PCDH1 transcripts display remarkable variability in expression of conserved intracellular signaling domains. Enhanced PCDH1 expression levels strongly correlate with differentiation of bronchial epithelial cells.
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Affiliation(s)
- Henk Koning
- Beatrix Children's Hospital, University Medical Center Groningen, Groningen, The Netherlands
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Spiess PC, Deng B, Hondal RJ, Matthews DE, van der Vliet A. Proteomic profiling of acrolein adducts in human lung epithelial cells. J Proteomics 2011; 74:2380-94. [PMID: 21704744 DOI: 10.1016/j.jprot.2011.05.039] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 05/20/2011] [Accepted: 05/26/2011] [Indexed: 02/01/2023]
Abstract
Acrolein (2,3-propenal) is a major indoor and outdoor air pollutant originating largely from tobacco smoke or organic combustion. Given its high reactivity, the adverse effects of inhaled acrolein are likely due to direct interactions with the airway epithelium, resulting in altered epithelial function, but only limited information exists to date regarding the primary direct cellular targets for acrolein. Here, we describe a global proteomics approach to characterize the spectrum of airway epithelial protein targets for Michael adduction in acrolein-exposed bronchial epithelial (HBE1) cells, based on biotin hydrazide labeling and avidin purification of biotinylated proteins or peptides for analysis by LC-MS/MS. Identified protein targets included a number of stress proteins, cytoskeletal proteins, and several key proteins involved in redox signaling, including thioredoxin reductase, thioredoxin, peroxiredoxins, and glutathione S-transferase π. Because of the central role of thioredoxin reductase in cellular redox regulation, additional LC-MS/MS characterization was performed on purified mitochondrial thioredoxin reductase to identify the specific site of acrolein adduction, revealing the catalytic selenocysteine residue as the target responsible for enzyme inactivation. Our findings indicate that these approaches are useful in characterizing major protein targets for acrolein, and will enhance mechanistic understanding of the impact of acrolein on cell biology.
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Affiliation(s)
- Page C Spiess
- Department of Pathology, University of Vermont, Burlington, VT 05405, USA
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Wu X, Peters-Hall JR, Bose S, Peña MT, Rose MC. Human bronchial epithelial cells differentiate to 3D glandular acini on basement membrane matrix. Am J Respir Cell Mol Biol 2011; 44:914-21. [PMID: 20724555 PMCID: PMC3135851 DOI: 10.1165/rcmb.2009-0329oc] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 08/18/2010] [Indexed: 11/24/2022] Open
Abstract
To create a model system that investigates mechanisms resulting in hyperplasia and hypertrophy of respiratory tract submucosal glands, we developed an in vitro three-dimensional (3D) system wherein normal human bronchial epithelial (HBE) cells differentiated into glandular acini when grown on a basement membrane matrix. The differentiation of primary HBE cells into glandular acini was monitored temporally by light microscopy. Apoptosis-induced lumen formation was observed by immunofluorescence analysis. The acinar cells expressed and secreted MUC5B mucin (marker for glandular mucous cells) and lysozyme, lactoferrin, and zinc-α2-glycoprotein (markers for glandular serous cells) at Day 22. β-Tubulin IV, a marker for ciliated cells, was not detected. Expression of mucous and serous cell markers in HBE glandular acini demonstrated that HBE cells grown on a basement membrane matrix differentiated into acini that exhibit molecular characteristics of respiratory tract glandular acinar cells. Inhibition studies with neutralizing antibodies resulted in a marked decrease in size of the spheroids at Day 7, demonstrating that laminin (a major component of the basement membrane matrix), the cell surface receptor integrin α6, and the cell junction marker E-cadherin have functional roles in HBE acinar morphogenesis. No significant variability was detected in the average size of glandular acini formed by HBE cells from two normal individuals. These results demonstrated that this in vitro model system is reproducible, stable, and potentially useful for studies of glandular differentiation and hyperplasia.
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Affiliation(s)
- Xiaofang Wu
- Center for Genetic Medicine Research and Division of Otolaryngology, Children's National Medical Center; and Departments of Biochemistry and Molecular Biology, Otolaryngology, and Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington D.C
| | - Jennifer R. Peters-Hall
- Center for Genetic Medicine Research and Division of Otolaryngology, Children's National Medical Center; and Departments of Biochemistry and Molecular Biology, Otolaryngology, and Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington D.C
| | - Sumit Bose
- Center for Genetic Medicine Research and Division of Otolaryngology, Children's National Medical Center; and Departments of Biochemistry and Molecular Biology, Otolaryngology, and Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington D.C
| | - Maria T. Peña
- Center for Genetic Medicine Research and Division of Otolaryngology, Children's National Medical Center; and Departments of Biochemistry and Molecular Biology, Otolaryngology, and Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington D.C
| | - Mary C. Rose
- Center for Genetic Medicine Research and Division of Otolaryngology, Children's National Medical Center; and Departments of Biochemistry and Molecular Biology, Otolaryngology, and Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington D.C
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Freishtat RJ, Watson AM, Benton AS, Iqbal SF, Pillai DK, Rose MC, Hoffman EP. Asthmatic airway epithelium is intrinsically inflammatory and mitotically dyssynchronous. Am J Respir Cell Mol Biol 2011; 44:863-9. [PMID: 20705942 PMCID: PMC3135846 DOI: 10.1165/rcmb.2010-0029oc] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 07/12/2010] [Indexed: 12/30/2022] Open
Abstract
Asthma is an inflammatory condition for which anti-inflammatory glucocorticoids are the standard of care. However, similar efficacy has not been shown for agents targeting inflammatory cells and pathways. This suggests a noninflammatory cell contributor (e.g., epithelium) to asthmatic inflammation. Herein, we sought to define the intrinsic and glucocorticoid-affected properties of asthmatic airway epithelium compared with normal epithelium. Human primary differentiated normal and asthmatic airway epithelia were cultured in glucocorticoid-free medium beginning at -48 hours. They were pulsed with dexamethasone (20 nM) or vehicle for 2 hours at -26, -2, +22, and +46 hours. Cultures were mechanically scrape-wounded at 0 hours and exposed continuously to bromodeoxyuridine (BrdU). Cytokine secretions were analyzed using cytometric bead assays. Wound regeneration/mitosis was analyzed by microscopy and flow cytometry. Quiescent normal (n = 3) and asthmatic (n = 6) epithelia showed similar minimal inflammatory cytokine secretion and mitotic indices. After wounding, asthmatic epithelia secreted more basolateral TGF-β1, IL-10, IL-13, and IL-1β (P < 0.05) and regenerated less efficiently than normal epithelia (+48 h wound area reduction = [mean ± SEM] 50.2 ± 7.5% versus 78.6 ± 7.7%; P = 0.02). Asthmatic epithelia showed 40% fewer BrdU(+) cells at +48 hours (0.32 ± 0.05% versus 0.56 ± 0.07% of total cells; P = 0.03), and those cells were more dyssynchronously distributed along the cell cycle (52 ± 10, 25 ± 4, 23 ± 7% for G1/G0, S, and G2/M, respectively) than normal epithelia (71 ± 1, 12 ± 2, and 17 ± 2% for G1/G0, S, and G2/M, respectively). Dexamethasone pulses improved asthmatic epithelial inflammation and regeneration/mitosis. In summary, we show that inflammatory/fibrogenic cytokine secretions are correlated with dyssynchronous mitosis upon injury. Intermittent glucocorticoids simultaneously decreased epithelial cytokine secretions and resynchronized mitosis. These data, generated in an airway model lacking inflammatory cells, support the concept that epithelium contributes to asthmatic inflammation.
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Affiliation(s)
- Robert J Freishtat
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20010, USA.
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Hackett NR, Shaykhiev R, Walters MS, Wang R, Zwick RK, Ferris B, Witover B, Salit J, Crystal RG. The human airway epithelial basal cell transcriptome. PLoS One 2011; 6:e18378. [PMID: 21572528 PMCID: PMC3087716 DOI: 10.1371/journal.pone.0018378] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 03/05/2011] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The human airway epithelium consists of 4 major cell types: ciliated, secretory, columnar and basal cells. During natural turnover and in response to injury, the airway basal cells function as stem/progenitor cells for the other airway cell types. The objective of this study is to better understand human airway epithelial basal cell biology by defining the gene expression signature of this cell population. METHODOLOGY/PRINCIPAL FINDINGS Bronchial brushing was used to obtain airway epithelium from healthy nonsmokers. Microarrays were used to assess the transcriptome of basal cells purified from the airway epithelium in comparison to the transcriptome of the differentiated airway epithelium. This analysis identified the "human airway basal cell signature" as 1,161 unique genes with >5-fold higher expression level in basal cells compared to differentiated epithelium. The basal cell signature was suppressed when the basal cells differentiated into a ciliated airway epithelium in vitro. The basal cell signature displayed overlap with genes expressed in basal-like cells from other human tissues and with that of murine airway basal cells. Consistent with self-modulation as well as signaling to other airway cell types, the human airway basal cell signature was characterized by genes encoding extracellular matrix components, growth factors and growth factor receptors, including genes related to the EGF and VEGF pathways. Interestingly, while the basal cell signature overlaps that of basal-like cells of other organs, the human airway basal cell signature has features not previously associated with this cell type, including a unique pattern of genes encoding extracellular matrix components, G protein-coupled receptors, neuroactive ligands and receptors, and ion channels. CONCLUSION/SIGNIFICANCE The human airway epithelial basal cell signature identified in the present study provides novel insights into the molecular phenotype and biology of the stem/progenitor cells of the human airway epithelium.
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Affiliation(s)
- Neil R. Hackett
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Renat Shaykhiev
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Matthew S. Walters
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Rui Wang
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Rachel K. Zwick
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Barbara Ferris
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Bradley Witover
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Jacqueline Salit
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Ronald G. Crystal
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America
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Yu D, Walters DM, Zhu L, Lee PK, Chen Y. Vanadium pentoxide (V(2)O(5)) induced mucin production by airway epithelium. Am J Physiol Lung Cell Mol Physiol 2011; 301:L31-9. [PMID: 21531775 DOI: 10.1152/ajplung.00301.2010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Exposure to environmental pollutants has been linked to various airway diseases and disease exacerbations. Almost all chronic airway diseases such as chronic obstructive pulmonary disease and asthma are caused by complicated interactions between gene and environment. One of the major hallmarks of those diseases is airway mucus overproduction (MO). Excessive mucus causes airway obstruction and significantly increases morbidity and mortality. Metals are major components of environmental particulate matters (PM). Among them, vanadium has been suggested to play an important role in PM-induced mucin production. Vanadium pentoxide (V(2)O(5)) is the most common commercial source of vanadium, and it has been associated with occupational chronic bronchitis and asthma, both of which are MO diseases. However, the underlying mechanism is not entirely clear. In this study, we used both in vitro and in vivo models to demonstrate the robust inductions of mucin production by V(2)O(5). Furthermore, the follow-up mechanistic study revealed a novel v-raf-1 murine leukemia viral oncogene homolog 1-IKK-NF-κB pathway that mediated V(2)O(5)-induced mucin production. Most interestingly, the reactive oxygen species and the classical mucin-inducing epidermal growth factor receptor (EGFR)-MAPK pathway appeared not to be involved in this process. Thus the V(2)O(5)-induced mucin production may represent a novel EGFR-MAPK-independent and environmental toxicant-associated MO model. Complete elucidation of the signaling pathway in this model will not only facilitate the development of the treatment for V(2)O(5)-associated occupational diseases but also advance our understanding on the EGFR-independent mucin production in other chronic airway diseases.
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Affiliation(s)
- Dongfang Yu
- Division of Translational Biology, the Hamner Institutes for Health Research, Brody School of Medicine, East Carolina University, North Carolina, USA
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Lee YC, Oslund KL, Thai P, Velichko S, Fujisawa T, Duong T, Denison MS, Wu R. 2,3,7,8-Tetrachlorodibenzo-p-dioxin-induced MUC5AC expression: aryl hydrocarbon receptor-independent/EGFR/ERK/p38-dependent SP1-based transcription. Am J Respir Cell Mol Biol 2010; 45:270-6. [PMID: 20971882 DOI: 10.1165/rcmb.2010-0313oc] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent environmental toxicant. Epidemiological studies have associated TCDD exposure with the development of chronic obstructive pulmonary disease, which is manifested by mucous/goblet cell hyperplasia. The purpose of this research was to elucidate the pathway/mechanisms that lead to TCDD-induced gene expression in both primary normal human bronchial epithelial cells and an immortalized cell line, HBE1, under air-liquid interface conditions. TCDD exposure induced a time-dependent elevation of MUC5AC mRNA and protein synthesis, and cytochrome p450 1A1 (CYP1A1) expression in these cells. Treatment with an aryl hydrocarbon receptor antagonist had no effect on TCDD-induced MUC5AC expression, but significantly suppressed CYP1A1 induction. However, treatments with inhibitors of signaling pathways and the expression of dominant negative mutants of epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK) and p38, but not the inhibition of c-Jun N-terminal kinase pathway, abrogated MUC5AC induction, but not that of CYP1A1. These effects also occurred at the MUC5AC promoter-reporter level using the chimeric construct for a transient transfection study. Western blot analysis confirmed the phosphorylation of activated EGFR, ERK, and p38 signaling molecules, but not the c-Jun N-terminal kinase, in cells after TCDD exposure. Specificity protein 1 (Sp1) phosphorylation also occurred in cells after TCDD exposure. Both MUC5AC expression and the promoter activity were inhibited by mithramycin A, an inhibitor specific to Sp1-based transcription. These results lead to the conclusion that TCDD induced MUC5AC expression through a noncanonical aryl hydrocarbon receptor-independent, EGFR/ERK/p38-mediated signaling pathway-mediated/Sp1-based transcriptional mechanism.
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Affiliation(s)
- Yong C Lee
- Center for Comparative Respiratory Biology and Medicine, University of California at Davis, 95616, USA
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Watson AM, Benton AS, Rose MC, Freishtat RJ. Cigarette smoke alters tissue inhibitor of metalloproteinase 1 and matrix metalloproteinase 9 levels in the basolateral secretions of human asthmatic bronchial epithelium in vitro. J Investig Med 2010; 58:725-9. [PMID: 20305574 DOI: 10.231/jim.0b013e3181db874e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Asthma, a major cause of chronic lung disease worldwide, has increased in prevalence in all age and ethnic groups, particularly in urban areas where cigarette smoking is common. Cigarette smoke (CS) significantly impacts the development of asthma and is strongly associated with increased asthma-related morbidity. PURPOSE To evaluate bioinformatic analyses predicting that CS would alter expression of tissue inhibitor of metalloproteinase (TIMP) 1 and matrix metalloproteinase (MMP) 9 in asthmatic epithelium. METHODS Primary differentiated normal (n = 4) and asthmatic (n = 4) human respiratory epithelia on collagen-coated Transwells at air-liquid interface were exposed for 1 hour to CS condensate (CSC) or hydrogen peroxide (H2O2). Tissue inhibitor of metalloproteinase 1 and MMP-9 protein levels were measured at 24 hours by enzyme-linked immunosorbent assay in cell lysates and in apical and basolateral secretions. RESULTS Tissue inhibitor of metalloproteinase 1 and MMP-9 levels in the apical secretions of normal and asthmatic epithelia were unchanged after exposure to CSC and H2O2. However, CSC increased TIMP-1 levels in the basolateral secretions of both normal and asthmatic epithelia, but decreased MMP-9 levels only in asthmatic basolateral secretions, resulting in a 2.5-fold lower MMP-9/TIMP-1 ratio that corresponded to decreased MMP-9 activity in CS-exposed asthmatic basolateral secretions. CONCLUSIONS These data validate our prior bioinformatic analyses predicting that TIMP-1 plays a role in the stress response to CS and indicate that asthmatics exposed to CS may be more susceptible to MMP-9-mediated airway remodeling. This is in agreement with the current paradigm that a reduction in the MMP-9/TIMP-1 ratio is a milieu that favors subepithelial airway remodeling in chronic asthma.
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Affiliation(s)
- Alan M Watson
- Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC, USA
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Oslund KL, Adamson G, Wu R. Evaluation of MUC5AC expression and upregulation in airway epithelial cells of horses. Am J Vet Res 2010; 71:690-6. [PMID: 20513186 DOI: 10.2460/ajvr.71.6.690] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To isolate and culture primary equine airway epithelial cells in vitro and elucidate the major cytokines involved in expression of the gel-forming mucin gene MUC5AC in horses. SAMPLE POPULATION 12 tracheas obtained within 5 hours after euthanasia from horses free from respiratory tract disease. PROCEDURES Tracheal rings were digested overnight in 0.2% protease, and dissociated airway epithelial cells were grown in a serum-free defined medium at an air-liquid interface until confluence was achieved. Differentiated airway epithelial cells were treated with a panel of recombinant equine cytokines followed by quantitative reverse transcriptase PCR assay for mRNA of equine MUC5AC and the control gene glyceraldehyde 3-phosphate dehydrogenase. Cultures were incubated in the presence of isohelenin, a nuclear factor kappaB-DNA-binding inhibitor, to investigate transcriptional regulation of MUC5AC. RESULTS Light and electron microscopy revealed a differentiated epithelium with ciliated cells, nonciliated mucous cells, and basal-like cells. Recombinant equine tumor necrosis factor-alpha was the major mediator in the cytokine panel that significantly increased MUC5AC mRNA by a factor of 5 in a dose- and time-dependent manner. This enhancement was attenuated by isohelenin. CONCLUSIONS AND CLINICAL RELEVANCE Data suggested that a nuclear factor KB-based transcriptional mechanism is involved in induction of MUC5AC expression by tumor necrosis factor-A. Understanding the molecular mechanism of cytokine-enhanced MUC5AC expression in horses may lead to better treatment options and understanding of the pathogenesis of equine pulmonary diseases.
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Affiliation(s)
- Karen L Oslund
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine and Center for Comparative Respiratory Biology and Medicine, School of Medicine, University of California-Davis, Davis, CA 95616, USA.
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Dvorak A, Tilley AE, Shaykhiev R, Wang R, Crystal RG. Do airway epithelium air-liquid cultures represent the in vivo airway epithelium transcriptome? Am J Respir Cell Mol Biol 2010; 44:465-73. [PMID: 20525805 DOI: 10.1165/rcmb.2009-0453oc] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Human airway epithelial cells cultured in vitro at the air-liquid interface (ALI) form a pseudostratified epithelium that forms tight junctions and cilia, and produces mucin. These cells are widely used in models of differentiation, injury, and repair. To assess how closely the transcriptome of ALI epithelium matches that of in vivo airway epithelial cells, we used microarrays to compare the transcriptome of human large airway epithelial cells cultured at the ALI with the transcriptome of large airway epithelium obtained via bronchoscopy and brushing. Gene expression profiling showed that global gene expression correlated well between ALI cells and brushed cells, but with some differences. Gene expression patterns mirrored differences in proportions of cell types (ALIs have higher percentages of basal cells, whereas brushed cells have higher percentages of ciliated cells), that is, ALI cells expressed higher levels of basal cell-related genes, and brushed cells expressed higher levels of cilia-related genes. Pathway analysis showed that ALI cells had increased expression of cell cycle and proliferation genes, whereas brushed cells had increased expression of cytoskeletal organization and humoral immune response genes. Overall, ALI cells provide a good representation of the in vivo airway epithelial transcriptome, but for some biologic questions, the differences between in vitro and in vivo environments need to be considered.
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Affiliation(s)
- Anna Dvorak
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
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Linderholm AL, Onitsuka J, Xu C, Chiu M, Lee WM, Harper RW. All-trans retinoic acid mediates DUOX2 expression and function in respiratory tract epithelium. Am J Physiol Lung Cell Mol Physiol 2010; 299:L215-21. [PMID: 20511343 DOI: 10.1152/ajplung.00015.2010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
DUOX1 and DUOX2 are members of the NADPH oxidase family that are specifically regulated to produce hydrogen peroxide in epithelia of the thyroid, gastrointestinal tract, and respiratory tract. The determinants of DUOX1 or DUOX2 expression in various tissues have not been established. Using respiratory tract epithelial cells as a model, we investigated changes in DUOX mRNA and protein expression during the first 10 days of differentiation. By comparing a respiratory tract cell line, HBE1, with primary tracheobronchial epithelial (TBE) cells, we determined that DUOX2 was significantly expressed only in cell conditions that included all-trans retinoic acid (ATRA). In HBE1 cells, DUOX2 mRNA increased 6-fold after ATRA treatment. Similarly, ATRA induced a 19-fold increase in DUOX2 mRNA expression in primary TBE cells with parallel increases in DUOX protein and DUOX-mediated H(2)O(2) production as well. In addition, DUOX2 induction by rhinovirus required the presence of ATRA. ATRA had no effect on DUOX1 expression for all the conditions studied. Our data indicate that for respiratory epithelial cells, ATRA is important in the regulation of DUOX2 expression, function, and rhinovirus-mediated DUOX2 inducibility.
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Air–Liquid Interface Culture of Nasal Epithelial Cells on Denuded Amniotic Membranes. Cell Mol Bioeng 2010. [DOI: 10.1007/s12195-010-0118-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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Bautista MV, Chen Y, Ivanova VS, Rahimi MK, Watson AM, Rose MC. IL-8 Regulates Mucin Gene Expression at the Posttranscriptional Level in Lung Epithelial Cells. THE JOURNAL OF IMMUNOLOGY 2009; 183:2159-66. [DOI: 10.4049/jimmunol.0803022] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Ahmad S, Ahmad A, Dremina ES, Sharov VS, Guo X, Jones TN, Loader JE, Tatreau JR, Perraud AL, Schöneich C, Randell SH, White CW. Bcl-2 suppresses sarcoplasmic/endoplasmic reticulum Ca2+-ATPase expression in cystic fibrosis airways: role in oxidant-mediated cell death. Am J Respir Crit Care Med 2009; 179:816-26. [PMID: 19201925 DOI: 10.1164/rccm.200807-1104oc] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Modulation of the activity of sarcoendoplasmic reticulum calcium ATPase (SERCA) can profoundly affect Ca(2+) homeostasis. Although altered calcium homeostasis is a characteristic of cystic fibrosis (CF), the role of SERCA is unknown. OBJECTIVES This study provides a comprehensive investigation of expression and activity of SERCA in CF airway epithelium. A detailed study of the mechanisms underlying SERCA changes and its consequences was also undertaken. METHODS Lung tissue samples (bronchus and bronchiole) from subjects with and without CF were evaluated by immunohistochemistry. Protein and mRNA expression in primary non-CF and CF cells was determined by Western and Northern blots. MEASUREMENTS AND MAIN RESULTS SERCA2 expression was decreased in bronchial and bronchiolar epithelia of subjects with CF. SERCA2 expression in lysates of polarized tracheobronchial epithelial cells from subjects with CF was decreased by 67% as compared with those from subjects without CF. Several non-CF and CF airway epithelial cell lines were also probed. SERCA2 expression and activity were consistently decreased in CF cell lines. Adenoviral expression of mutant F508 cystic fibrosis transmembrane regulator gene (CFTR), inhibition of CFTR function pharmacologically (CFTR(inh)172), or stable expression of antisense oligonucleotides to inhibit CFTR expression caused decreased SERCA2 expression. In CF cells, SERCA2 interacted with Bcl-2, leading to its displacement from caveolae-related domains of endoplasmic reticulum membranes, as demonstrated in sucrose density gradient centrifugation and immunoprecipitation studies. Knockdown of SERCA2 using siRNA enhanced epithelial cell death due to ozone, hydrogen peroxide, and TNF-alpha. CONCLUSIONS Reduced SERCA2 expression may alter calcium signaling and apoptosis in CF. These findings decrease the likelihood of therapeutic benefit of SERCA inhibition in CF.
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Affiliation(s)
- Shama Ahmad
- Department of Pediatrics, National Jewish Medical and Research Center, A440, 1400 Jackson Street, Denver, CO 80206, USA.
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Zhu L, Lee PK, Lee WM, Zhao Y, Yu D, Chen Y. Rhinovirus-induced major airway mucin production involves a novel TLR3-EGFR-dependent pathway. Am J Respir Cell Mol Biol 2008; 40:610-9. [PMID: 18978302 DOI: 10.1165/rcmb.2008-0223oc] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mucociliary clearance is a critical innate defense system responsible for clearing up invading pathogens including bacteria and virus. Although the right amount of mucus is good, excessive mucus causes airway obstruction and tends to precipitate disease symptoms. Rhinovirus (RV) is a common cold virus that causes asthma and chronic obstructive pulmonary disease exacerbation. Mucus overproduction has been linked to the pathogenesis of RV-induced diseases and disease exacerbations. However, the molecular mechanism is not clear. In this study, using one of the major airway mucin-MUC5AC as marker, we found that both major and minor groups of RV induced mucin production in primary human epithelial cells and cell line. RV1A (a minor group of RV) could induce mucous cell metaplasia in vivo. Viral replication was needed for RV-induced mucin expression, and this induction was also dependent on TLR3, suggesting the involvement of double-stranded (ds) RNA signaling. Indeed, dsRNA alone could also induce mucin expression. TLR3-mediated mucin induction was negatively regulated by MyD88, and only partially dependent on TRIF, which suggests a departure from well-documented TLR3 signaling paradigm that mediates inflammatory and other innate defense gene inductions. In addition, TLR3 signaling activated epidermal growth factor receptor (EGFR) through inductions of the expression of EGFR ligands (transforming growth factor-alpha and amphiregulin), which in turn activated EGFR-ERK signaling and mucin expression through an autocrine/paracrine loop. This novel coupling of antiviral defense machinery (i.e., TLR3) and major epithelial proliferation/repair pathway (i.e., EGFR) might play an important role in viral-induced airway remodeling and airway disease exacerbation.
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Affiliation(s)
- Lingxiang Zhu
- Division of Translational Biology, the Hamner Institutes for Health Research, Research Triangle Park, North Carolina, USA
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Isolation and culture of primary equine tracheal epithelial cells. In Vitro Cell Dev Biol Anim 2008; 44:179-84. [PMID: 18594938 DOI: 10.1007/s11626-008-9099-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Accepted: 03/27/2008] [Indexed: 10/21/2022]
Abstract
Culture of airway epithelial cells is a useful model to investigate physiology of airway epithelia and airway disease mechanisms. In vitro models of airway epithelial cells are established for various species. However, earlier published method for isolation and culture of equine tracheal epithelial cells requires significant improvements. In this report, the development of a procedure for efficient isolation, characterization, culture, and passage of primary equine tracheal epithelial cells are described. Epithelial cells were isolated from adult equine trachea by exposing and stripping the mucosal epithelium from the adjacent connective tissue and smooth muscle. The tissue was minced and dissociated enzymatically using 0.25% trypsin-ethylenediaminetetraacetic acid (EDTA) solution for 2 h at 37 degrees C. Cells were collected by sieving and centrifugation, and contaminating fibroblasts were removed by differential adhesion. This procedure resulted in a typical yield of 1 x 10(7) cytokeratin-positive epithelial cells per gram tracheal lining tissue. Viability was 95% by trypan blue exclusion and isolates contained approximately 94% cytokeratin-positive cells of epithelial origin. Cells seeded at a density of 6.9 x 10(4) cells/cm2 in serum-free airway epithelial cell growth medium formed monolayers near confluency within a week. Confluent cells were dissociated using dispase II and first passages (P1) and second passages (P2) were successfully established in serum-free medium. Collagen coating of tissue culture flask was not required for cell adhesion, and cultures could be maintained at the level of P2 over 30 d. In the present study, we could establish a high-yield protocol for isolation and culture of equine tracheal epithelial cells that can serve for in vitro/ex vivo studies on the (patho-)physiology of equine airway disease as well as pharmacological and toxicological targets relevant to airway diseases.
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