Antigen and antibody attachment in ELISA for Aspergillus fumigatus IgG antibodies

Four commercial antigen extracts of Aspergillus fumigatus were evaluated for use in a rapid enzyme-linked immunosorbent assay (ELISA) for anti-A. fumigatus IgG. Initial binding of both somatic and culture filtrate preparations to a polyvinyl chloride solid phase was concentration dependent and increased with incubation time. Antigen binding to the solid phase was reproducible. Binding of A. fumigatus precipitin-positive serum to bound antigen was rapid. All four A. fumigatus antigens demonstrated similar dose-response curves when tested against pooled sera containing a high titre of A. fumigatus antibodies. Detectable activity in precipitin test-negative sera decreased rapidly with dilution. All the antigen preparations were found to be suitable for ELISA procedures and permit the rapid determination of IgG antibodies to A. fumigatus.