title: IL-17 producing T cells correlate with polysensitization but not with bronchial hyperresponsiveness in patients with allergic rhinitis.
abstract: BACKGROUND
  Th2-type T cell response has a considerable role in atopic diseases. The involvement of Th17 and IL-17 in atopy process provided new understanding of allergic diseases. Bronchial hyperresponsiveness is quite common in allergic rhinitis. We aimed to explore the expression of IL-17 producing CD3+ CD4+ T cells in peripheral blood of rhinitic patients, with/without bronchial hyperresponsiveness and sensitized to common allergens, as this relationship has not been examined.
  
  
  METHODS
  Sixty one patients with allergic rhinitis and thirty controls were examined. IL-17 producing T cells were detected by flow cytometry, IL-17, IL-4 and IL-13 levels in peripheral blood were evaluated by ELISA. Bronchial hyperresponsiveness was investigated with methacholine challenge test. Atopy was evaluated by skin prick tests with common allergens.
  
  
  RESULTS
  IL-17 producing T cell percentage of AR group was significantly higher: 2.59 ± 1.32 than in controls 1.24 ± 0.22, (p = 0.001). Significant sex related difference in CD3+ CD4+ IL-17 T cells was observed: respectively in male patients versus female 3.15 ± 1.8% and 2.31 ± 0.9%, (p = 0.02). Rhinitics had greater bronchodilator responses compared to controls (p = 0.001), however the percentages of T cells in both groups appeared equal. Serum IL-17 levels in AR group were significantly higher (5.10 ± 4.40) pg/ml than in controls (3.46 ±1.28) pg/ml, (p = 0.04). IL-4 levels (0.88 ± 1.27) and IL-13 levels (3.14 ± 5.85) in patients were significantly higher than in control's (0.54 ± 0.10) pg/ml, (p = 0.001) and (1.19 ± 0.64) pg/ml; (p = 0.001) respectively.The percentages of T cells in patients sensitized to 5 allergens (group I) were significantly lower (1.91 ± 0.62) than those sensitized to more than 5 allergens (group II) (2.91 ± 1.5) (p = 0.004).
  
  
  CONCLUSIONS
  The observed higher levels of IL-17 producing T cells in polysensitized males suggest a role of IL-17 in pathogenesis of AR. The higher airway responsiveness in AR may not be Th17 dependent. The higher serum values of IL-17, IL-4 and IL-13 demonstrate the presence of cytokine balance in atopic diseases.
authors.affiliation: Department of Clinical Laboratory, Clinical Immunology and Allergology, Medical University of Pleven, Pleven, Bulgaria. vmtsvetkova@abv.bg.
authors.forename: Vanya M
authors.initials: VM
authors.lastname: Tsvetkova-Vicheva
authors.forename: Svetla P
authors.initials: SP
authors.lastname: Gecheva
authors.forename: Regina
authors.initials: R
authors.lastname: Komsa-Penkova
authors.forename: Angelika S
authors.initials: AS
authors.lastname: Velkova
authors.forename: Tcvetan H
authors.initials: TH
authors.lastname: Lukanov