Characterization of a second major antigen Ag 13 (antigen C) of Aspergillus fumigatus and investigation of its immunological reactivity.
A second major antigen of Aspergillus fumigatus (Ag 13) has been identified and characterized as a 70 kD, heat-labile component which is able to bind to the lectin, concanavalin A. Ag 13 proved to be identical to the previously recognized C antigen, known to possess chymotryptic activity. A monospecific antiserum to Ag 13 has been affinity purified and used to develop a sandwich ELISA for measuring levels of Ag 13 specific IgG antibodies in patients' sera. Although all ABPA sera (25/25) had significantly raised levels, some aspergilloma sera (2/5) had only very low levels; of the control sera, 10/10 fungal atopics were negative, but 5/12 farmer's lung sera had low but positive values of Ag 13 specific IgG, i.e. sensitivity 100%, specificity 80%. Ag 13 is therefore a diagnostically important component of A. fumigatus and the antigen-specific ELISA may be of importance for the improved detection of disease-specific antibodies.
Harvey
C
C
Department of Allergy and Clinical Immunology, Brompton Hospital, London, UK.
Longbottom
J L
JL
D000946:Antigens, Fungal / Q000032:analysis / Q000302:isolation & purification*; D001229:Aspergillosis, Allergic Bronchopulmonary / Q000276:immunology*; D001232:Aspergillus fumigatus / Q000276:immunology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007123:Immunoelectrophoresis, Two-Dimensional
D000946:Antigens, Fungal