title: Recruitment of CD1a+ Langerhans cells to the nasal mucosa in seasonal allergic rhinitis and effects of topical corticosteroid therapy.
abstract: BACKGROUND
  Local antigen presentation may be necessary for both primary and recall T-cell responses to grass pollen in hay fever patients. We examined the effect of seasonal allergen exposure on nasal mucosal antigen-presenting cell (APC) populations and the effects of topical corticosteroid therapy.
  
  
  METHODS
  Nasal biopsies were collected from 46 grass pollen-sensitive seasonal rhinitis patients before the grass-pollen season. A second biopsy was collected during the pollen season, when patients had received 6 weeks' treatment with either fluticasone propionate (200 microg, twice daily) or placebo. Cell populations in biopsy sections were quantified by immunocytochemistry.
  
  
  RESULTS
  Significant increases in submucosal and epithelial CD1a+ Langerhans cells, but not CD68 + macrophages or CD20 + B cells, were observed during the pollen season. Seasonal increases in CD1a+ Langerhans cells were inhibited by corticosteroid therapy.
  
  
  CONCLUSIONS
  Recruitment of CD1a+ Langerhans cells to the nasal mucosa during natural seasonal allergen exposure may contribute to local T cell responses. Topical corticosteroids may act, at least in part, by inhibiting effective allergen presentation to T cells through inhibition of recruitment of Langerhans cells to the nasal mucosa.
authors.affiliation: Upper Respiratory Medicine, Imperial College School of Medicine at the National Heart and Lung Institute of Medicine at the National Heart and Lung Institute, London, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Till
authors.forename: M R
authors.initials: MR
authors.lastname: Jacobson
authors.forename: F
authors.initials: F
authors.lastname: O'Brien
authors.forename: S R
authors.initials: SR
authors.lastname: Durham
authors.forename: A
authors.initials: A
authors.lastname: KleinJan
authors.forename: W J
authors.initials: WJ
authors.lastname: Fokkens
authors.forename: S
authors.initials: S
authors.lastname: Juliusson
authors.forename: O
authors.initials: O
authors.lastname: Löwhagen
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000730:Androstadienes / Q000008:administration & dosage* / Q000627:therapeutic use; D015703:Antigens, CD / Q000032:analysis; D018949:Antigens, CD1 / Q000032:analysis*; D018951:Antigens, CD20 / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D001706:Biopsy; D002465:Cell Movement / Q000187:drug effects; D005260:Female; D000068298:Fluticasone; D006801:Humans; D007150:Immunohistochemistry; D007801:Langerhans Cells / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D008264:Macrophages / Q000276:immunology / Q000473:pathology; D008297:Male; D009297:Nasal Mucosa / Q000276:immunology* / Q000473:pathology; D006109:Poaceae / Q000276:immunology; D011058:Pollen / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy* / Q000276:immunology*; D000097382:CD68 Molecule
chemical_list: D000730:Androstadienes; D015703:Antigens, CD; D018949:Antigens, CD1; D018951:Antigens, CD20; D015214:Antigens, Differentiation, Myelomonocytic; D000068298:Fluticasone; C419393:CD1a antigen; C067980:CD68 antigen, human; D000097382:CD68 Molecule