SERUM LEVEL OF SOLUBLE INTERLEUKIN-2 RECEPTOR IN PATIENTS WITH SEASONAL ALLERGIC RHINITIS

The rate of release of the soluble form of interleukin-2 receptor (sol uble IL-2R) reflects T cell activation in vivo. Since T lymphocytes pl ay a central role in respiratory allergic disorders, the measurement o f serum levels of soluble IL-2R may be useful in analysing the disease state of allergic disorders. The study has aimed at investigating the seasonal changes in serum soluble IL-2R in 81 patients with seasonal allergic rhinitis due to Japanese cedar pollens, with special referenc e to the effect of anti-allergic pharmacotherapy and immunotherapy. Se rum samples were obtained twice from each patient, before and during t he pollen season, and all the serum samples were simultaneously used f or determination of soluble IL-2R and cedar pollen-specific immunoglob ulin E (IgE). Seasonal elevation in soluble IL-2R was not associated w ith the good clinical outcome but was associated with the poor clinica l outcome, irrespective of pharmacotherapy or immunotherapy. Additiona lly, successful immunotherapy suppressed seasonal elevation of serum s oluble IL-2R more strongly than successful pharmacotherapy, and season al increase rates in soluble IL-2R were inversely correlated with the duration of immunotherapy. Seasonal increase rates in soluble IL-2R we re significantly correlated with seasonal increase rates in specific I gE in both the medication group and the immunotherapy patients. These results may suggest that seasonal changes in serum soluble IL-2R may s erve as an indicator for clinical outcome of seasonal allergic rhiniti s, that the magnitude of T cell activation could affect specific IgE p roduction, and that T cell activation could be gradually modulated as immunotherapy proceeds. In conclusion, seasonal changes in serum solub le IL-2R may serve as an objective indicator for clinical outcome of s easonal allergic rhinitis.