Cellular immune activity of a galactomannan-protein complex from mycelia of Histoplasma capsulatum.
A galactomannan-protein complex was extracted from defatted mycelium of Histoplasma capsulatum with 0.25 N alkali at 25 C. It accounted for 7.5% of the cell dry weight in nondialyzable form and had a galactose-mannose ratio of 2:5. The complex containing 68% protein was separated into polysaccharide and glycoprotein components by ion-exchange chromatography. The galactomannan formed a single precipitate in immunodiffusion, sharing a common antigen with the glycoprotein which contained two precipitating antigens. The glycoprotein elicited delayed-type hypersensitivity in guinea pigs as measured by skin-test and macrophage migration inhibitory factor assay, with 5 mug resulting in 86% specific inhibition. The galactomannan was skin-test negative, but 10 mug resulted in 80% specific inhibition of migration.
D000596:Amino Acids / Q000032:analysis; D000946:Antigens, Fungal / Q000302:isolation & purification; D002464:Cell Migration Inhibition; D002852:Chromatography, Ion Exchange; D005656:Fungal Proteins / Q000276:immunology; D005690:Galactose / Q000276:immunology; D006023:Glycoproteins / Q000276:immunology*; D006658:Histoplasma / Q000276:immunology*; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007111:Immunity, Cellular; D005779:Immunodiffusion; D008264:Macrophages / Q000276:immunology; D008358:Mannose / Q000276:immunology; D011134:Polysaccharides / Q000276:immunology*; D012882:Skin Tests
D000596:Amino Acids; D000946:Antigens, Fungal; D005656:Fungal Proteins; D006023:Glycoproteins; D011134:Polysaccharides; D008358:Mannose; D005690:Galactose