An ex vivo model of severe asthma using reconstituted human bronchial epithelium

• Published in: Journal of allergy and clinical immunology Vol. 129; no. 5; pp. 1259 - 1266.e1
• Main Authors: Gras, Delphine, PhD, Bourdin, Arnaud, MD, PhD, Vachier, Isabelle, PhD, de Senneville, Laure, Bonnans, Caroline, PhD, Chanez, Pascal, MD, PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01.05.2012; Elsevier
• Subjects: Adult; Aged; Airway Remodeling; Allergy and Immunology; Arachidonate 5-lipoxygenase; Asthma; Asthma - immunology; Asthma - pathology; Asthma - physiopathology; asthma severity; Biological and medical sciences; Biopsy; Bronchi - pathology; Cell culture; Cell Culture Techniques; Cell Differentiation; Cells, Cultured; Differentiation; Disease Progression; Epithelial cells; Epithelium; Feasibility Studies; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Gene expression; Humans; Immunopathology; Inflammation; Interleukin 8; Interleukin-8 - genetics; Interleukin-8 - metabolism; Learning; Lipoxin A4; Lipoxins - genetics; Lipoxins - metabolism; Lipoxygenase; Lipoxygenase - genetics; Lipoxygenase - metabolism; Male; Medical sciences; Middle Aged; mucin; Mucins - metabolism; Mucus; resolution; Respiratory Mucosa - immunology; Respiratory Mucosa - pathology; Respiratory tract; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; Young Adult; Reticular basement membrane; LO; Enzyme-linked lectin assay; HSPBS; Epithelium; resolution; BAL; asthma severity; inflammation; Bronchoalveolar lavage; High-salt PBS; Lipoxin A 4; ELLA; Lipoxygenase; RBM; LXA 4; LXA4; Human; Immunopathology; Bronchus; Inflammation; Respiratory system; Respiratory tract; Immunology; Ex vivo; Models; Severe asthma
• ISSN: 0091-6749; 1097-6825
• DOI: 10.1016/j.jaci.2012.01.073

Background Structural changes to the airways are features of severe asthma. The bronchial epithelium facilitates this remodeling process. Learning about the changes that develop in the airway epithelium could improve our understanding of asthma pathogenesis and lead to new therapeutic approaches. Objective We sought to determine the feasibility and relevance of air-liquid interface cultures of bronchial epithelium derived from endobronchial biopsy specimens of patients with different severities of asthma for studying the airway epithelium. Methods Human bronchial epithelial cells derived from endobronchial biopsy specimens of patients with mild and severe asthma were maintained in culture for 21 days in an air-liquid interface to reproduce a fully differentiated airway epithelium. Initially, features of remodeling that included epithelial and subepithelial layers, as well as mucus production, were assessed in paraffin-embedded endobronchial biopsy specimens to evaluate morphologic characteristics of asthmatic patients’ epithelia. Ex vivo differentiated epithelia were then analyzed for morphology and function based on ultrastructural analysis, IL-8 release, lipoxin A4 generation, mucin production, and lipoxygenase gene expression. Results Morphologic and inflammatory imbalances initially observed in endobronchial biopsy specimens obtained from patients with severe or mild asthma persisted in the air-liquid interface reconstituted epithelium throughout the differentiation process to 21 days. Epithelium from patients with severe asthma produced greater levels of mucin, released more IL-8, and produced lower levels of lipoxin A4 than that from patients with mild asthma. Expression of 15-lipoxygenase 2 was increased in epithelium from patients with severe asthma, whereas expression levels of MUC5AC, MUC5B, 5-lipoxygenase, and 15-lipoxygeanse 1 were similar to those of patients with mild asthma. Conclusion Ex vivo cultures of fully differentiated bronchial epithelium from endobronchial biopsy specimens maintain inherent phenotypic differences specifically related to the severity of asthma.