Abstract
Circulating complexed IgE was investigated by gel filtration using Sephacryl S-300 superfine at both pH 8.0 and 3.2 in serum from a patient with bronchial asthma complicated by atopic dermatitis. In 97 cases, ranging from 3 to 13 years of age, serum IgE and 4% polyethylene glycol precipitated IgE levels were measured by paper radioimmunosorbent test. The rate of 4% polyethylene glycol precipitated IgE to serum IgE was calculated as PEG precipitated index (PP index) to exclude the effect of serum IgE levels. The following results were obtained: 1) Serum from a patient with bronchial asthma complicated by atopic dermatitis was fractionated by borate buffered saline, pH 8.0. Two peaks of IgE in monomeric and complexed or aggregated form were demonstrated. Next, serum from the same patient was fractinated by glycine HCI buffer, pH 3.2, in investigating macromolecular IgE, the complexed or aggregated form. The first peak of IgE in complexed or aggregated form by gel filtratiop at pH 8.0 was dissociated by filtration at pH 3.2. These results suggest that IgE immune complex exists in serum from patients with bronchial asthma complicated by atopic dermatitis. 2) In the bronchial asthma patients, IgE PP indices were at high levels compared with control subjects, but IgG and IgA PP indices were almost within normal range. 3) IgE PP indices in asthmatic children with attack were at significantly higher levels than in those without attack. These results suggest that circulating IgE immune complex may play etiological role in the pathogenesis of bronchial asthma.
