Antigens and allergens of Aspergillus fumigatus: I. Characterization by quantitative immunoelectrophoretic techniques

Both the IgG (precipitinogen) and IgE combining components of Aspergillus fumigatus have been studied by quantitative immunoelectrophoretic techniques with sera of patients with allergic bronchopulmonary aspergillosis and specific rabbit antisera. Considerable batch-to-batch variation in biochemical properties and in immunologic (both antigenic and allergenic) activity was revealed in identically prepared culture-filtrate antigens of the same strain of A. fumigatus. Profiles of crossed immunoelectrophoresis/crossed radioimmunoelectrophoresis appeared to vary qualitatively; however, the differences in antigenicity and allergenicity were demonstrated by crossed-line immunoelectrophoretic techniques to be essentially quantitative rather than qualitative in nature. Both types of activity were concentrated in the protein fraction obtained by salt precipitation, and little activity remained in the predominantly polysaccharide supernatant that accounted for >30% (dry weight) of the antigenic extract. Heat-stability studies demonstrated a varied pattern of denaturation. Certain allergenic components were stable to considerable heating, and the extracts so treated were still active on skin testing.