title: Imbalance of Th17 and T-regulatory cells in peripheral blood and synovial fluid in treatment naïve children with juvenile idiopathic arthritis.
abstract: OBJECTIVE
  The imbalance between Th17 and T regulatory cells (Tregs) may be a key event in development of autoimmunity. The problem is poorly explored in juvenile idiopathic arthritis (JIA) so far. In this study, peripheral blood (PB) and synovial fluid (SF) Tregs and Th17 cells from were assessed in untreated JIA children.
  
  
  METHODS
  In 50 children with JIA the PB or SF percentages of Tregs and Th17 cells were assessed by flow cytometry, in comparison with PB Tregs and Th17 cells from 28 healthy controls. Additionally, in both groups the levels of proinfammatory cytokines, such as interleukin (IL)-1β, IL -6, IL -17, IL -21, IL -23 and tumor necrosis factor α (TN F-α) were assessed using ELI SA method.
  
  
  RESULTS
  The proportion of JIA PB Th17 cells was significantly higher than in the controls (p = 0.01). Serum levels of IL -1β, IL -6, IL -17, IL -23 were also significantly higher in JIA (p = 0.011, p = 0.007, p = 0.008 and p = 0.023, respectively). The highest serum IL -6 levels were observed in oligoarthritis JIA (p = 0.031). Synovial fluid IL -21 concentration was distinctly higher in polyarticular JIA. Synovial fluid levels of TN F-α, IL -1β and IL -6 were significantly higher than in JIA PB (p = 0.038, p = 0.013 and p < 0.001, respectively). There was a significant correlation between IL -6 and PB Tregs (p = 0.02).
  
  
  CONCLUSIONS
  The results of this comprehensive analysis indicate a role of Th17 cell activation in the pathogenesis of JIA.
authors.affiliation: Department of Pediatric Cardiology and Rheumatology, Medical University of Lodz, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Szymańska-Kałuża
authors.affiliation: Department of Experimental Hematology, Medical University of Lodz, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Cebula-Obrzut
authors.affiliation: Department of Experimental Hematology, Medical University of Lodz, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Smolewski
authors.affiliation: Department of Pediatric Cardiology and Rheumatology, Medical University of Lodz, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Stanczyk
authors.affiliation: Department of Pediatric Cardiology and Rheumatology, Medical University of Lodz, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Smolewska
keywords: T-regulatory cells; Th17 cells; juvenile idiopathic arthritis; proinflammatory cytokines