YEARLY AND SEASONAL-CHANGES OF SPECIFIC IGE TO JAPANESE CEDAR POLLEN IN A YOUNG-POPULATION

Background: There have been no detailed long-term observations of the relationship between specific IgE production and stimulation by variou s naturally occurring allergens. Objective: This study was conducted t o elucidate the yearly and seasonal changes of specific IgE antibody p roduction to Japanese cedar pollen, an allergen of Japanese cedar poll inosis, in young adults. Methods: The numbers of Japanese cedar pollen were counted over a period of 9 years. Changes in the percentages of antibody carriers to Japanese cedar pollen and mite were examined duri ng these years, Changes in Japanese cedar pollen-specific IgE levels b etween a low exposure year and a high exposure year in individual subj ects were also investigated. Results: From 1987 to 1995, the percentag es of Japanese cedar pollen-IgE carriers varied from about 30% to 50% with the intensity of pollen stimulation, and carriers tended to incre ase yearly, The rates of anti-mite IgE carriers changed little. In the spring which is the pollen season, Japanese cedar pollen-IgE levels i n low exposure years were weaker than those in high exposure years in individual subjects, Levels in autumn, which is not the pollen season, showed equivalent levels in both high and low exposure years. Anti-mi te IgE levels in individual subjects varied little during these years. Conclusions: A long-term follow-up study supported that Japanese ceda r pollen-IgE production is mainly associated with the degree of allerg en exposure.