Effect of specific immunotherapy in eosinophil cationic protein release after specific nasal provocation

Abstract

Specific immunotherapy (SIT) is effective in the treatment of allergic rhinitis but its mechanisms of action are still not completely understood, particularly in regard to eosinophil activation mechanisms. The purpose of this research was to study if the inhibition of eosinophil activation, demonstrated through the reduction of eosinophil cationic protein [ECP] release, is involved in the therapeutic actions of specific immunotherapy. We analyzed ECP concentrations in nasal lavage fluid of 21 patients with allergic rhinitis, before and after specific nasal provocation. These results were compared to controls, treated without specific immunotherapy. ECP concentrations in nasal lavage fluid were significantly reduced after two years of specific injectable immunotherapy. These reductions were demonstrated both in pre-provocation [basal] values and after specific nasal provocation. Specific immunotherapy can reduce ECP in nasal lavage fluid of in house dust mite allergic rhinitis patients, both before and after allergen nasal challenge, with significant changes in the kinetic of ECP release, a fact which suggests that specific immunotherapy can influence eosinophil activation or its releasability.