[Circulating immune complexes in airborne allergy--a protective role?]

Circulating immune complexes (KI) were analyzed in 78 patients with airborne allergy and compared to 34 persons of control group. KI were isolated by precipitation with 3% polyethylene glycol. KI-IgG, KI-IgA, KI-IgM were measured by radial immunodiffusion, KI-IgE by an immunofluorometric assay. Staphylococcal Protein A (SpA) binding to KI was measured by ria. Relations between the level of various KI and the diagnosis of allergic disease, the kind of allergen (related also to the exposition) and the symptoms of atopy were evaluated. Serum levels of KI-IgE, KI-SpA, and KI-IgM were distinctly elevated in airborne allergy, with the positive correlation between KI-SpA and KI-IgM. KI-IgE were related to the kind of sensitizing allergen and to the exposition to the pollen allergens. Most distinct differences in KI level were observed not in relation to the kind of disease or of the sensitizing allergen, but in relation to the symptoms and intensiveness of atopy. Patients showing a greater number and intensiveness of symptoms exhibited higher levels of KI-SpA. However, one of the symptoms scored (dyspnea) was connected with the decreased level of KI-SpA in these patients. We interpret the results in favour of the hypothesis of the dual role of KI in airborne allergy. We propose a protective role for KI-Spa, which contain IgG and may bind IgE, thus protecting the target organs of allergy.