title: Polymorphisms in the interleukin-1 gene influence the stratum corneum interleukin-1 alpha concentration in uninvolved skin of patients with chronic irritant contact dermatitis.
abstract: BACKGROUND
  Interleukin (IL)-1 alpha and its receptor antagonist IL-1 ra play a role in skin inflammation. Several polymorphisms in the IL1 gene cluster, coding for IL-1 alpha, IL-1 ra, and IL-1 beta, influence their protein expression. Within this cluster, strong linkage disequilibrium has been shown.
  
  
  OBJECTIVE
  We studied the association between the polymorphisms IL1A-889 (C-->T) and IL1B-31 (T-->C) and the concentration of IL-1 alpha and IL-1 ra in the stratum corneum (SC).
  
  
  METHODS
  In 124 patients with chronic irritant contact dermatitis, we genotyped the IL1A-889 and IL1B-31 polymorphisms and determined the amount of IL-1 alpha and IL-1 ra on tape strips obtained from uninvolved skin of the volar forearm.
  
  
  RESULTS
  The SC IL-1 alpha concentration was 23% and 47% lower in subjects with IL1A-889 C/T genotype and T/T genotype, respectively, compared with wild-type genotype. In subjects with IL1B-31 C/C genotype, the IL-1 alpha concentration was 51% lower compared with C/T and T/T genotypes. The ratio IL-1 ra/IL-1 alpha increased twofold in IL1A-889 C/T genotype and threefold in T/T genotype compared with wild type.
  
  
  CONCLUSIONS
  We have shown a clear effect of IL1 genotype on protein expression in the SC. This altered expression may be responsible for the interindividual differences in the inflammatory response of the skin.
authors.affiliation: Coronel Institute of Occupational Health, Academic Medical Center, University of Amsterdam, 1100 DD Amsterdam, The Netherlands.
authors.forename: Cindy M
authors.initials: CM
authors.lastname: de Jongh
authors.forename: Liubov
authors.initials: L
authors.lastname: Khrenova
authors.forename: Sanja
authors.initials: S
authors.lastname: Kezic
authors.forename: Thomas
authors.initials: T
authors.lastname: Rustemeyer
authors.forename: Maarten M
authors.initials: MM
authors.lastname: Verberk
authors.forename: Swen M
authors.initials: SM
authors.lastname: John
mesh_terms: D000328:Adult; D000483:Alleles; D000704:Analysis of Variance; D002908:Chronic Disease; D004247:DNA / Q000032:analysis; D017453:Dermatitis, Irritant / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D004817:Epidermis / Q000378:metabolism*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000235:genetics / Q000378:metabolism*; D053582:Interleukin-1alpha / Q000235:genetics* / Q000378:metabolism; D053583:Interleukin-1beta / Q000235:genetics* / Q000378:metabolism; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide
chemical_list: D053590:Interleukin 1 Receptor Antagonist Protein; D053582:Interleukin-1alpha; D053583:Interleukin-1beta; D004247:DNA