Production and characterization of a murine monoclonal antibody to Aspergillus fumigatus antigen having IgG- and IgE-binding activity.

By employing hybridoma technology, a monoclonal antibody against Aspergillus fumigatus was produced. This antibody, isotyped as IgM k, reacted with 12 of 16 antigens extracted from 9 different A. fumigatus strains. This antibody also reacted with all 3 Aspergillus flavus antigens studied, but not with Aspergillus niger, Aspergillus terreus, Penicillium notatum or Candida albicans antigens. Western blot analysis indicated that this antibody reacted with two concanavalin A (Con-A) binding bands of the A. fumigatus antigen extract. The specific binding antigens were isolated using monoclonal antibody affinity chromatography. When used in immunoassay this fraction demonstrated strong IgG and IgE antibody-binding activities against patient sera. The antibody levels against the purified fraction were significantly higher in patients' sera than in normal controls. The purified fraction demonstrated comparable reactivity with the crude A. fumigatus extract against patient sera, but the former has the added advantage of being pure and standardizable for dependable and reproducible results.