title: Glucocorticoid sensitivity in Behçet's disease.
abstract: OBJECTIVE
  Glucocorticoid (GC) sensitivity is highly variable among individuals and has been associated with susceptibility to develop (auto-)inflammatory disorders. The purpose of the study was to assess GC sensitivity in Behçet's disease (BD) by studying the distribution of four GC receptor (GR) gene polymorphisms and by measuring in vitro cellular GC sensitivity.
  
  
  METHODS
  Healthy controls and patients with BD in three independent cohorts were genotyped for four functional GR gene polymorphisms. To gain insight into functional differences in in vitro GC sensitivity, 19 patients with BD were studied using two bioassays and a whole-cell dexamethasone-binding assay. Finally, mRNA expression levels of GR splice variants (GR-α and GR-β) were measured.
  
  
  RESULTS
  Healthy controls and BD patients in the three separate cohorts had similar distributions of the four GR polymorphisms. The Bcll and 9β minor alleles frequency differed significantly between Caucasians and Mideast and Turkish individuals. At the functional level, a decreased in vitro cellular GC sensitivity was observed. GR number in peripheral blood mononuclear cells was higher in BD compared with controls. The ratio of GR-α/GR-β mRNA expression levels was significantly lower in BD.
  
  
  CONCLUSIONS
  Polymorphisms in the GR gene are not associated with susceptibility to BD. However, in vitro cellular GC sensitivity is decreased in BD, possibly mediated by a relative higher expression of the dominant negative GR-β splice variant. This decreased in vitro GC sensitivity might play an as yet unidentified role in the pathophysiology of BD.
authors.affiliation: Department of Internal Medicine, Erasmus MC University Medical Center 's-Gravendijkwal 2303015 CE, Rotterdam The Netherlands.
authors.forename: R A M
authors.initials: RA
authors.lastname: Quax
authors.forename: J A M
authors.initials: JA
authors.lastname: van Laar
authors.forename: R
authors.initials: R
authors.lastname: van Heerebeek
authors.forename: K
authors.initials: K
authors.lastname: Greiner
authors.forename: E
authors.initials: E
authors.lastname: Ben-Chetrit
authors.forename: M
authors.initials: M
authors.lastname: Stanford
authors.forename: G R
authors.initials: GR
authors.lastname: Wallace
authors.forename: F
authors.initials: F
authors.lastname: Fortune
authors.forename: M
authors.initials: M
authors.lastname: Ghabra
authors.forename: M
authors.initials: M
authors.lastname: Soylu
authors.forename: J M W
authors.initials: JM
authors.lastname: Hazes
authors.forename: S W J
authors.initials: SW
authors.lastname: Lamberts
authors.forename: J H
authors.initials: JH
authors.lastname: Kappen
authors.forename: P M
authors.initials: PM
authors.lastname: van Hagen
authors.forename: J W
authors.initials: JW
authors.lastname: Koper
authors.forename: R A
authors.initials: RA
authors.lastname: Feelders
keywords: Behçet's syndrome; glucocorticoid sensitivity; single nucleotide polymorphism