Peripheral TH-17 cells in children with allergic rhinitis: preliminary report.

Th17 is a subset of T helper lymphocytes and exerts pro-inflammatory activities. Recently, it has been reported that serum IL-17 levels are high in the most severe patients with birch allergy studied both outside and during the pollen season. This study aims to compare the frequency of peripheral IL-17-producing T cells in children with allergic rhinitis and in healthy controls. Ten children with allergic rhinitis and 5 healthy non-allergic subjects were evaluated. Th17 were evaluated by intracellular staining in ex-vivo T cell compartment. Ex- vivo PBMNC evaluation showed that allergic patients had higher frequencies of IL-17 producing T cells, both concerning CD4+ and CD8+ cells. In particular, there is a subset co-expressing IL-17 and IFN-gamma both for CD4+ and CD8+ cells. In conclusion, this preliminary study suggests a possible role of Th-17 cells in the response to allergens in children