Serum-soluble Fas antigen level in patients with allergic rhinitis: its relation to specific immunotherapy.

There have been conflicting reports on the relationship between Fas/Fas ligand-mediated apoptosis and allergic response. Specific immunotherapy (SIT) is widely used for treatment of allergic diseases. It has long been apparent that SIT results in a reduction in antigen-specific lymphoproliferation, but it is unclear by what mechanism T-cell responses are inhibited by SIT in vivo. In this study, we examined serum-soluble Fas (sFas) levels in patients with allergic rhinitis and healthy subjects. We also examined the effect of SIT on sFas level. Seventy-two patients with allergic rhinitis and 20 healthy subjects were included in this study. Twenty-eight patients were newly diagnosed and 44 patients were treated with SIT for a 5-year or 7-year duration. Serum sFas levels were measured by a sandwich enzyme-linked immunoassay. Mean serum sFas level was 7931 +/- 2861 pg/mL in newly diagnosed patients with allergic rhinitis during the pollen season, 8426 +/- 2846 pg/mL in patients with allergic rhinitis treated by SIT for a 5-year duration, 8490 +/- 2256 pg/mL in patients with allergic rhinitis treated by SIT for a 7-year duration, and 7493 +/- 3450 pg/mL in healthy subjects. Serum sFas level was not found to be significantly different among the study groups (p > 0.05). These findings suggest that there is no relation between sFas level and the etiopathogenesis of allergic inflammation in patients with allergic rhinitis and mechanism of action of SIT.