Abstract
Changes of serum IgE levels and IgE antibody titers were studied in 40 bronchial asthmatic patients in an asthma home. Radioimmunosorbent test (RIST) or radioallergosorbent test (RAST) were employed. All patients were house-dust sensitive, and antibody titers against house dust measured by RAST were above score 2. Thirty patients were on hyposensitization therapy for house dust and ten were not. The results were as follows. 1. The dose-response curves of RAST using paper disc-coupled antigen and sera from D. pteronyssinus-sensitized patients and reference serum were linear and paralleled with each other when % total count (radioactivity of samples × 100 divided bu total radioactivity added) and IgE antibody titers were plotted on a log-log scale. However, the dose-response curve between paper disc-coupled antigen and sera sensitized by house dust was not linear and formed a plateau in a high antibody titer region. The deficiency of house dust antigens which were coupled to paper disc was suggested. 2. Serum IgE antibody titer against mold was higher in summer than in spring. Serum IgE antibody titer against D. farinae was higher in winter than in spring. Serum total IgE levels were higher in summer than in spring. These results suggested seasonal changes in IgE antibody titers. 3. Serum IgE antibody titer against house dust in the hyposensitization group showed no significant tendency of decreasing IgE antibody titer. 4. Serum total IgE levels in the hyposensitization group showed no obvious tendency of decreasing total IgE levels. 5. The RAST score in patients hyposensitized by house dust showed few changes, but the concentration of allergents required to produce a positive reaction increased in about half of the patients. This might suggest a reduced skin reactivity after hyposensitization therapy.
