title: Resistin-like molecule-β is induced following bronchoconstriction of asthmatic airways.
abstract: OBJECTIVE
  Resistin-like molecule-β (RELM-β) is a necessary and sufficient stimulus for airway remodelling in animal models of asthma, but until recently, its role in human disease had not been investigated. The hypothesis that RELM-β expression would increase with increasing asthma severity and further increase following acute bronchoconstrictor challenges has been examined.
  
  
  METHODS
  Bronchial biopsies from healthy subjects and patients with mild and severe asthma were immunostained for RELM-β, as were airway biopsies obtained in mild asthmatics before and 4 days after repeated inhalation challenges with either allergen, methacholine or methacholine preceded by salbutamol as a control. Bronchial brushings were also evaluated for RELM-β mRNA.
  
  
  RESULTS
  RELM-β immunoreactivity, which co-localized to airway epithelial cells, increased with disease severity; healthy volunteers, median per cent epithelial area 1.98%, mild asthma 3.49% and severe asthma 5.89% (P < 0.001 between groups). RELM-β immunoreactivity significantly and inversely correlated in asthma with forced expiratory volume in 1 s % predicted (P = 0.005). Acute changes in immunoexpression were evident after repeated inhalation challenge with allergen (2.15 % to 4.35 % (P = 0.01)) and methacholine (4.21 % to 6.16 % (P = 0.01)) but did not change in the salbutamol/methacholine challenge group. These changes correlated with change in basement membrane thickness (r = 0.38, P = 0.02). Epithelial RELM-β gene expression was not altered in asthma.
  
  
  CONCLUSIONS
  RELM-β may play an important role not only in animal models of airway remodelling, but also in human airway pathology.
authors: Academic Unit of Clinical and Experimental Sciences, Southampton University Faculty of Medicine, NIHR Respiratory Biomedical Research Unit and Wellcome Trust Clinical Research Facility, Southampton, UK. c.l.grainge@southampton.ac.uk
authors: Christopher
authors: C
authors: Grainge
authors: Valdeep
authors: V
authors: Dulay
authors: Jonathan
authors: J
authors: Ward
authors: David
authors: D
authors: Sammut
authors: Elizabeth
authors: E
authors: Davies
authors: Benjamin
authors: B
authors: Green
authors: Laurie
authors: L
authors: Lau
authors: Laura
authors: L
authors: Cottey
authors: Hans-Michael
authors: HM
authors: Haitchi
authors: Donna E
authors: DE
authors: Davies
authors: Peter H
authors: PH
authors: Howarth
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D056151:Airway Remodeling / Q000276:immunology*; D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000276:immunology / Q000378:metabolism*; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000276:immunology*; D001999:Bronchoscopy; D006801:Humans; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D016210:Methacholine Chloride; D008875:Middle Aged; D055815:Young Adult
chemical_list: D000485:Allergens; D036341:Intercellular Signaling Peptides and Proteins; C486574:RETNLB protein, human; D016210:Methacholine Chloride