title: Accumulation of dendritic cells and increased CCL20 levels in the airways of patients with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) is characterized by chronic airway inflammation. It is unclear if dendritic cells (DC) participate in this inflammatory process.
  
  
  OBJECTIVE
  To evaluate the presence of DC in small airways of patients with COPD.
  
  
  METHODS
  We evaluated DC infiltration in small airways by immunohistochemistry in patients with COPD (stage I-IV), never-smokers, and smokers without COPD. Chemokine ligand 20 (CCL20, the most potent chemokine in attracting DC) was determined in total lung by RT-PCR and in induced sputum by enzyme-linked immunsorbent assay. Chemokine receptor 6 (CCR6, the receptor for CCL20) expression on human pulmonary DC was evaluated by RT-PCR and flow cytometry.
  
  
  RESULTS
  There is a significant increase in DC number in the epithelium (p = 0.007) and adventitia (p = 0.009) of small airways of patients with COPD compared with never-smokers and smokers without COPD. DC number in epithelium and adventitia increases along with disease severity. CCL20 mRNA expression in total lung and CCL20 protein levels in induced sputum are significantly higher in patients with COPD compared with never-smokers (p = 0.034 for CCL20 mRNA and p = 0.0008 for CCL20 protein) and smokers without COPD (p = 0.016 for CCL20 mRNA and p = 0.001 for CCL20 protein). DC isolated from human lung express CCR6 both at mRNA and at protein level.
  
  
  CONCLUSIONS
  This is the first description of airway infiltration by DC in COPD. Moreover, interaction between CCL20 and CCR6 provides a possible mechanism for accumulation of DC in the lungs in COPD.
authors.affiliation: Department of Respiratory Diseases, Ghent University Hospital, B-9000 Ghent, Belgium. M.DemedtsIngelK@UGent.be
authors.forename: Ingel K
authors.initials: IK
authors.lastname: Demedts
authors.forename: Ken R
authors.initials: KR
authors.lastname: Bracke
authors.forename: Geert
authors.initials: G
authors.lastname: Van Pottelberge
authors.forename: Dries
authors.initials: D
authors.lastname: Testelmans
authors.forename: Geert M
authors.initials: GM
authors.lastname: Verleden
authors.forename: Frank E
authors.initials: FE
authors.lastname: Vermassen
authors.forename: Guy F
authors.initials: GF
authors.lastname: Joos
authors.forename: Guy G
authors.initials: GG
authors.lastname: Brusselle
mesh_terms: D000368:Aged; D054418:Chemokine CCL20; D019742:Chemokines, CC / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006801:Humans; D008168:Lung / Q000276:immunology* / Q000473:pathology; D019402:Macrophage Inflammatory Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000276:immunology* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D054399:Receptors, CCR6; D019707:Receptors, Chemokine / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D013183:Sputum / Q000737:chemistry / Q000276:immunology
chemical_list: C108355:CCL20 protein, human; C106311:CCR6 protein, human; D054418:Chemokine CCL20; D019742:Chemokines, CC; D019402:Macrophage Inflammatory Proteins; D012333:RNA, Messenger; D054399:Receptors, CCR6; D019707:Receptors, Chemokine