| Sera from 38 patients with invasive aspergillosis were tested by Western blotting for the presence of antibodies to antigens of Aspergillus fumigatus present in a mycelial extract of the organism. All of the sera had antibodies to an antigen of molecular weight 58,000 as determined by SDS-PAGE. This antigen contains carbohydrate and protein since it was stained by both Coomassie blue and periodic acid-Schiff stains and it bound to the lectin, concanavalin A. Therefore, it is being called a glycoprotein. The glycoprotein was purified by immunoaffinity chromatography employing 2-2-9, a monoclonal antibody produced against the 58kDa antigen. Analysis of the purified antigen by gas-liquid chromatography revealed the presence of mannose, galactose and glucose residues in a 2:1:2 ratio. The ratio of protein to carbohydrate is 1.16:1. It is a slightly acidic glycoprotein containing relatively high quantities of glutamic and aspartic acids, glycine, alanine, serine and threonine. It also contains phosphate groups as part of its structure.;Eight monoclonal antibodies were produced against the 58kDa glycoprotein. 2-7, 2-12 and 2-14 are of the IgM class and 2-2-1, 2-2-4, 2-2-6, 2-2-9 and 2-2-13 are all IgG;In these studies, a potential serodiagnostic marker for invasive aspergillosis was identified and characterized. The specific reagents which were prepared may facilitate the development of a reliable diagnostic test for invasive aspergillosis. |
