Increased intraepithelial (CD103+) CD8+ T cells in the airways of smokers with and without chronic obstructive pulmonary disease

• Published in: Immunobiology (1979) Vol. 218; no. 2; pp. 225 - 231
• Main Authors: Mikko, M, Forsslund, H, Cui, L, Grunewald, J, Wheelock, Å.M, Wahlström, J, Sköld, C.M
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier GmbH 01.02.2013
• Subjects: Adult; Advanced Basic Science; Airway epithelium; Allergy and Immunology; Antigens, CD - metabolism; Bronchoalveolar lavage; CD8-Positive T-Lymphocytes - immunology; Cell Proliferation; Cell Separation; Chronic bronchitis; Disease Progression; Ex-smokers; Female; Flow Cytometry; Forkhead Transcription Factors - metabolism; Humans; Integrin alpha Chains - metabolism; Male; Medicin och hälsovetenskap; Middle Aged; Pulmonary Disease, Chronic Obstructive - etiology; Pulmonary Disease, Chronic Obstructive - immunology; Regulatory T cell; Respiratory Mucosa - immunology; Smoking - adverse effects; Smoking Cessation; T-Lymphocyte Subsets - immunology; T-Lymphocytes, Regulatory - immunology; residual volume; RV; forced expiratory volume in 1 s; forced vital capacity; Airway epithelium; BAL; FOXP3; carbon monoxide diffusing capacity; MFI; FVC; FEV 1; median fluorescence intensity; DLCO; Bronchoalveolar lavage; Regulatory T cell; Ex-smokers; forkhead box P3; Chronic bronchitis; COPD; chronic obstructive pulmonary disease; FEV1
• ISSN: 0171-2985; 1878-3279; 1878-3279
• DOI: 10.1016/j.imbio.2012.04.012

Abstract T cells are accumulated in the lungs of chronic obstructive pulmonary disease (COPD) patients. Intraepithelial T cells, expressing the integrin αE (CD103) β7, and regulatory T cells have been implicated in pathogenesis of the disease. We asked whether COPD patients and smokers have altered frequencies of these T cells and if their phenotypes differ. A total of 40 never-smokers, 40 smokers with normal lung function and 38 COPD patients (GOLD I and II), of which 11 were ex-smokers, were included. T cells in bronchoalveolar lavage (BAL) fluid and peripheral blood were analysed for the expression of CD103, FOXP3 and markers of activation and differentiation using multi-colour flow cytometry. Smokers, regardless of airway obstruction, had significantly more CD8+CD103+ cells in their BAL fluid compared to never-smokers but less of those cells were CD27 + CD69−. Smokers, in particular those with chronic bronchitis, had a higher percentage of CD4 + FOXP3+ T-regulatory BAL cells compared to never-smokers and COPD ex-smokers. Chronic cigarette smoking leads to an accumulation of CD8+ T cells with an altered phenotype in the airway epithelium. The increased frequency of regulatory T cells may influence the ability to regulate smoke-induced inflammation which could be decisive for disease development. Our results further indicate a reversibility of smoke-induced changes.