title: Epidermal Expression of Filaggrin/Profilaggrin Is Decreased in Atopic Dermatitis: Reverse Association With Mast Cell Tryptase and IL-6 but Not With Clinical Severity.
abstract: BACKGROUND
  A decrease in filaggrin expression contributes to the pathogenesis of atopic dermatitis (AD) and can be modified by inflammatory factors.
  
  
  OBJECTIVE
  The aim of this study was to determine the correlation of (pro)filaggrin (filaggrin and profilaggrin) expression with clinical severity in AD and with mast cell (MC) tryptase, chymase, and IL-6.
  
  
  METHODS
  Punch biopsies were collected from 17 patients with moderate-to-severe AD and from 10 psoriatic patients. Atopic dermatitis severity was measured using different clinical parameters. (Pro)filaggrin, MC tryptase, chymase, and IL-6 were stained using immunohistochemical, enzymehistochemical, and sequential double-staining methods.
  
  
  RESULTS
  (Pro)filaggrin expression was lower in the lesional than in the nonlesional granular layer in AD and was correlated negatively with itch severity but not with other severity parameters. (Pro)filaggrin expression was also decreased in the psoriatic lesions. In AD, (pro)filaggrin expression correlated negatively with the number of tryptase MCs in the nonlesional granular layer and with IL-6 MCs in both the nonlesional and lesional granular layers.
  
  
  CONCLUSIONS
  (Pro)filaggrin expression is decreased in AD and is reversely associated with MC tryptase and IL-6. However, it does not associate with disease severity, and it was also decreased in psoriasis.
authors.affiliation: From the *Department of Dermatology, University of Eastern Finland and Kuopio University Hospital; †Institute of Biomedicine, Anatomy and Biomater Centre, University of Eastern Finland; and ‡Cancer Center of Eastern Finland, Kuopio, Finland.
authors.forename: Tiina
authors.initials: T
authors.lastname: Ilves
authors.forename: Virpi
authors.initials: V
authors.lastname: Tiitu
authors.forename: Mireille-Maria
authors.initials: MM
authors.lastname: Suttle
authors.forename: Jari Vilho
authors.initials: JV
authors.lastname: Saarinen
authors.forename: Ilkka Tapani
authors.initials: IT
authors.lastname: Harvima
mesh_terms: D000328:Adult; D000368:Aged; D053818:Chymases / Q000032:analysis; D003876:Dermatitis, Atopic / Q000150:complications / Q000378:metabolism*; D004817:Epidermis / Q000737:chemistry*; D005260:Female; D000091344:Filaggrin Proteins; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis*; D007381:Intermediate Filament Proteins / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011537:Pruritus / Q000209:etiology / Q000378:metabolism; D011565:Psoriasis / Q000378:metabolism; D012720:Severity of Illness Index; D053802:Tryptases / Q000032:analysis*; D055815:Young Adult
chemical_list: C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D015850:Interleukin-6; D007381:Intermediate Filament Proteins; D053818:Chymases; D053802:Tryptases