Decreased numbers of metachromatic cells in nasal swabs in Japanese cedar pollinosis following sublingual immunotherapy

Background and Objective Nasal symptoms were reduced following allergen‐specific sublingual immunotherapy (SLIT) for allergic rhinitis. The mechanisms underlying the effectiveness of SLIT for Japanese cedar pollinosis are poorly understood. We studied changes in the numbers of metachromatic cells, eosinophils, and neutrophils following SLIT for Japanese cedar pollinosis. Methods Nasal swabs were taken in the preseason (n = 32) and in pollinosis season (n = 49) from subjects given sublingual drop immunotherapy for an average duration of 1.5 years. The numbers of metachromatic cells (mast cells and basophils), eosinophils and neutrophils were determined and compared with those from untreated subjects in preseason (n = 65) and in season (n = 54). Results SLIT subjects had a significantly reduced frequency of moderate to most severe symptoms in comparison to untreated subjects in preseason (P
The mechanisms underlying the effectiveness of sublingual immunotherapy (SLIT) for Japanese cedar pollinosis are poorly understood. One of mechanisms is a reduction of the number of metachromatic cells and eosinophils.