title: Mucin expression in peripheral airways of patients with chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  To study the expression of mucins in peripheral airways in patients with chronic obstructive pulmonary disease (COPD).
  
  
  RESULTS
  Peripheral lung sections from smokers with COPD (n = 9) and age-matched controls including smokers (n = 11) and lifelong non-smokers with normal lung function (n = 6) were stained with alcian blue, periodic acid-Schiff (PAS) and by immunohistochemistry of mucins (MUC): MUC2, MUC4, MUC5AC, MUC5B and MUC6. Histochemical staining and immunoreactivity of bronchiolar epithelium were graded and the presence or absence of stained mucus in the bronchiolar lumen was evaluated. There were no differences in alcian blue and PAS epithelial staining between the three groups. Intraluminal PAS staining was significantly more frequent among COPD subjects (P < 0.05). The expression of MUC5AC was significantly higher in the bronchiolar epithelium of patients with COPD (P < 0.05). Within the bronchiolar lumen, the predominant mucin was MUC5B. Intraluminal MUC5B was significantly more frequent among COPD patients (P < 0.05).
  
  
  CONCLUSIONS
  COPD is specifically associated with increased expression of MUC5B in the bronchiolar lumen and of the mucin MUC5AC in the bronchiolar epithelium. These changes in mucin production in the peripheral airways may contribute to the pathophysiology of COPD.
authors.affiliation: Centro di Ricerca su Asma e BPCO, University of Ferrara, Ferrara, Italy. crm@unife.it
authors.forename: G
authors.initials: G
authors.lastname: Caramori
authors.forename: C
authors.initials: C
authors.lastname: Di Gregorio
authors.forename: I
authors.initials: I
authors.lastname: Carlstedt
authors.forename: P
authors.initials: P
authors.lastname: Casolari
authors.forename: I
authors.initials: I
authors.lastname: Guzzinati
authors.forename: I M
authors.initials: IM
authors.lastname: Adcock
authors.forename: P J
authors.initials: PJ
authors.lastname: Barnes
authors.forename: A
authors.initials: A
authors.lastname: Ciaccia
authors.forename: G
authors.initials: G
authors.lastname: Cavallesco
authors.forename: K F
authors.initials: KF
authors.lastname: Chung
authors.forename: A
authors.initials: A
authors.lastname: Papi
mesh_terms: D000368:Aged; D001980:Bronchi / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D055262:Mucin-2; D055257:Mucin-5B; D009077:Mucins / Q000235:genetics / Q000378:metabolism*; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism*; D012907:Smoking / Q000009:adverse effects
chemical_list: C524625:MUC2 protein, human; C524578:MUC5B protein, human; D055262:Mucin-2; D055257:Mucin-5B; D009077:Mucins