title: Isolation and partial characterization of the heterophile antigen of infectious mononucleosis from bovine erythrocytes.
abstract: The heterophile antigen (Paul-Bunnell antigen, PBA) of infectious mononucleosis was isolated by extraction of an aqueous suspension of bovine erythrocyte stromata with chloroform-methanol (2:1). The upper aqueous layer contained gangliosides, PBA, and a high-molecular-weight glycoprotein. PBA and gangliosides were separated from the high-molecular-weight glycoprotein by extraction of lyophilized upper layer with chloroform-methanol solvents. Separation of PBA from gangliosides was carried out by chromatography on DEAE-cellulose with chloroform-methanol solvents. PBA appeared to be a minor glycoprotein component of the erythrocyte membrane and had both hydrophobic and hydrophilic properties. It was soluble in either organic or aqueous solvents. On SDS-polyacrylamide gel electrophoresis, it migrated as a single component that stained for protein with Coomassie blue, for carbohydrate with periodic acid-Schiff reagent, and for lipid with oil red 0; it had an apparent molecular weight of 26,000. It was composed of 62% protein with major amino acids; glutamic acid, proline, glycine, isoleucine, leucine, and threonine (158, 116, 98, 90, 85, and 82 residues per 1,000 residues, respectively). Carbohydrate content was 9.2% with major sugar constituents: sialic acid, galactosamine, and galactose. Serologic activity of PBA was destroyed by pronase but not by trypsin.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D015478:Antigens, Heterophile / Q000032:analysis / Q000302:isolation & purification*; D002417:Cattle; D004910:Erythrocyte Membrane / Q000276:immunology; D004912:Erythrocytes / Q000276:immunology*; D005732:Gangliosides / Q000097:blood / Q000276:immunology; D006023:Glycoproteins / Q000097:blood / Q000276:immunology; D005779:Immunodiffusion; D007244:Infectious Mononucleosis / Q000276:immunology*; D008565:Membrane Proteins / Q000276:immunology / Q000302:isolation & purification; D008970:Molecular Weight; D011402:Pronase; D012995:Solubility; D014357:Trypsin
chemical_list: D000596:Amino Acids; D015478:Antigens, Heterophile; D005732:Gangliosides; D006023:Glycoproteins; D008565:Membrane Proteins; D014357:Trypsin; D011402:Pronase