title: Mite-antigen avoidance can reduce bronchial epithelial shedding in allergic asthmatic children.
abstract: BACKGROUND
  Asthma is characterized by bronchial hyperresponsiveness (BHR), bronchial mucosa inflammation and airway epithelial damage.
  
  
  OBJECTIVE
  This study was designed to evaluate the effect of mite avoidance on bronchial epithelial shedding in asthmatic children sensitized to Dermatophagoides.
  
  
  METHODS
  The percentages of airway epithelial cells and eosinophil have been counted in samples obtained by hypertonic saline-induced sputum before and after a period of antigen avoidance in an Alpine environment (1756 m). The degree of bronchial hyperresponsiveness to methacholine was also evaluated.
  
  
  RESULTS
  After avoidance the median (lower, Q1, and upper, Q3, quartile) percentage of epithelial cells in the sputum decreased significantly from 3.50 [0.50;6.98] to 0 [0;0.5] (P=0.012) and eosinophil percentage decreased from 1 [0;5.25] to 0 [0,1.5] (P<0.05). Median (Q1,Q3) PC20 increased significantly from 2.75 [1.53;7.5] to 3.25 [1.65;15.25] mg/ mL (P=0.038). After 3 weeks of re-exposure to mite the epithelial median (Q1,Q3) percentage raised to 3.90 [1.5;6] (P = 0.027), eosinophils to 1.5 [0;3.00] (NS) and PC20 was 5.25 [1.68;14.50] (NS).
  
  
  CONCLUSIONS
  Exposure to house dust mite antigen can induce airway epithelial shedding even in subjects with low eosinophil airway infiltration, thus supporting the idea that epithelial damage in asthmatics sensitized to Dermatophagoides may be due to a proteolytic activity of the mite major antigens.
authors.affiliation: Clinica Pediatrica, Università di Verona, Italy.
authors.forename: G L
authors.initials: GL
authors.lastname: Piacentini
authors.forename: L
authors.initials: L
authors.lastname: Vicentini
authors.forename: P
authors.initials: P
authors.lastname: Mazzi
authors.forename: M
authors.initials: M
authors.lastname: Chilosi
authors.forename: L
authors.initials: L
authors.lastname: Martinati
authors.forename: A L
authors.initials: AL
authors.lastname: Boner
mesh_terms: D000293:Adolescent; D000485:Allergens; D000531:Altitude; D000818:Animals; D000941:Antigens / Q000378:metabolism; D001249:Asthma / Q000473:pathology*; D001980:Bronchi / Q000473:pathology*; D016535:Bronchial Hyperreactivity; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D002648:Child; D004391:Dust; D010450:Endopeptidases / Q000378:metabolism; D004804:Eosinophils / Q000473:pathology; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D016210:Methacholine Chloride; D008925:Mites / Q000276:immunology*; D013183:Sputum / Q000166:cytology / Q000276:immunology
chemical_list: D000485:Allergens; D000941:Antigens; D016085:Bronchoconstrictor Agents; D004391:Dust; D016210:Methacholine Chloride; D010450:Endopeptidases