Primary interaction between antibody and components of Alternaria. I. Immunology and chemical characteristics of labeled antigens.

Components were isolated from Alternaria tenuis and its culture filtrate, and were radiolabeled with 123-I. The labeled antigenic components had a high polysaccharide content as determined by staining patterns following electrophoresis in polyacrylamide gels and by inactivation with sodium metaperiodate. A primary binding test was employed to detect and measure serum antibodies to the components from A. tennuis. This procedure was more sensitive in detecting antibodies that bound to antigens than were comparable tests dependent upon precipitin types of reactions. The labeled components of A. tenuis cross-reacted or shared antigens with 3 other species of molds: Stemphylium sp., Curvularia sp., Aspergillus fumigatus, but not with a variety of other fungal and nonfungal materials.