Serum detection of a carbohydrate antigen of Trichosporon beigelii that cross-reacts with the capsular glucuronoxylomannan (GXM) of Cryptococcus neoformans is used as a diagnostic marker in disseminated trichosporonosis. We isolated and purified the cross-reactive polysaccharide antigen from Trichosporon beigelii, strain TCM. Immunochemical characterization of this carbohydrate antigen revealed that it shares antigenic determinant(s) with the capsular GXM of C. neoformans. It was a cell-associated, high molecular weight acidic polysaccharide which was released into the culture medium during growth in vitro. T. beigelii released 96-fold less polysaccharide into the culture supernatant than a clinical isolate of C. neoformans. Qualitative chemical analysis as determined by high-performance anion-exchange chromatography revealed that the polysaccharide was composed of mannose, xylose, glucose and glucuronic acid. Nuclear magnetic resonance spectroscopic analyses of native and modified polysaccharides suggested the presence of O-acetyl groups. The presence of O-acetyl and glucuronyl epitopes was confirmed serologically using epitope-specific antibodies. T. beigelii polysaccharide produced a precipitation line of partial identity with cryptococcal anti-GXM serum by immunodiffusion. Thus, the cell-associated carbohydrate antigen of T. beigelii is immunochemically similar to the GXM of C. neoformans and may play a role in pathogenesis.
|Original language||English (US)|
|Number of pages||6|
|Journal||Immunology and Infectious Diseases|
|State||Published - Dec 1 1996|
- Cryptococcus neoformans
- Trichosporon beigelii
ASJC Scopus subject areas