title: Higher frequencies of CD161+ circulating T lymphocytes in allergic rhinitis patients compared to healthy donors.
abstract: BACKGROUND
  Th17 is a subset of T-helper lymphocytes that produce proinflammatory cytokines, mainly IL-17. Serum IL-17 is increased in allergic patients and relates to clinical severity. Recently, it has been reported that CD161 is a highly upregulated gene in Th17 clones and all IL-17-producing cells are contained in CD161(+) T cells. This study aimed at comparing the frequency of peripheral CD161(+) T cells in patients with allergic rhinitis (AR) and in healthy controls and at relating CD161 expression with symptom severity.
  
  
  METHODS
  Forty-four patients with AR and 29 healthy non-allergic subjects were evaluated. CD161 expression was evaluated on CD3(+), CD4(+) and CD8(+) cells by double immunofluorescence staining and fluorescence activated cell sorter analysis. Symptom severity was assessed by the Visual Analogue Scale.
  
  
  RESULTS
  Allergic patients showed a significantly higher frequency of CD3(+)CD161(+), CD4(+)CD161(+) and CD8(+)CD161(+) cells than healthy non-allergic subjects (p < 0.0001). Moreover, the expression of CD161 cells was significantly related to clinical severity.
  
  
  CONCLUSIONS
  This study provides evidence that a higher frequency of CD161(+) T cells is present in the peripheral blood of AR patients.
authors.affiliation: Molecular Oncology and Angiogenesis Unit, National Institute for Cancer Research, Genoa, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Poggi
authors.forename: Paolo
authors.initials: P
authors.lastname: Canevali
authors.forename: Miriam
authors.initials: M
authors.lastname: Contatore
authors.forename: Giorgio
authors.initials: G
authors.lastname: Ciprandi
mesh_terms: D000328:Adult; D017252:CD3 Complex / Q000096:biosynthesis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D006801:Humans; D018655:Lymphocyte Count; D008297:Male; D055651:NK Cell Lectin-Like Receptor Subfamily B / Q000096:biosynthesis / Q000097:blood*; D006255:Rhinitis, Allergic, Seasonal / Q000097:blood / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D058504:Th17 Cells / Q000276:immunology
chemical_list: D017252:CD3 Complex; D055651:NK Cell Lectin-Like Receptor Subfamily B