title: Serum IL-9 levels depend on allergen exposure: preliminary study.
abstract: BACKGROUND
  Th9 is a new T cell subset characterized by interleukin 9 (IL-9) production. Serum IL-9 levels are related to symptom severity in patients with allergic rhinitis (AR). This study aimed at investigating whether IL-9 may depend on allergen exposure.
  
  
  METHODS
  35 AR patients (16 males, mean age 33.2 years) with monosensitization to Parietaria were studied when symptomatic; 38 AR patients (22 males, mean age 30.9 years) with monosensitization to birch were recruited at the same time, but were symptom free. Serum IL-9 was assayed in all patients.
  
  
  RESULTS
  Patients with Parietaria allergy and exposed to allergen had higher serum IL-9 levels than patients with birch allergy and not exposed to allergen (p<0.05).
  
  
  CONCLUSIONS
  This preliminary study shows that serum IL-9 levels may depend on allergen exposure: symptomatic patients with pollen-induced AR, evaluated during the pollen season, have higher values than patients studied outside the pollen season and without symptoms.
authors.affiliation: Department of Internal Medicine, Azienda Ospedaliera Universitaria San Martino, University of Genoa, Genoa, Italy. gio.cip@libero.it
authors.forename: Giorgio
authors.initials: G
authors.lastname: Ciprandi
authors.forename: Mara
authors.initials: M
authors.lastname: De Amici
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Castellazzi
authors.forename: Maria Angela
authors.initials: MA
authors.lastname: Tosca
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Marseglia
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology / Q000276:immunology / Q000503:physiopathology*; D016906:Interleukin-9 / Q000097:blood*; D008297:Male; D032403:Parietaria / Q000276:immunology*; D011058:Pollen / Q000276:immunology*; D006255:Rhinitis, Allergic, Seasonal / Q000209:etiology / Q000276:immunology / Q000503:physiopathology*; D012621:Seasons; D012720:Severity of Illness Index
chemical_list: D000485:Allergens; D016906:Interleukin-9