Molecular identification of T cell-specific antigens on human T lymphocytes and thymocytes.
We have identified membrane glycoproteins which carry T cell-specific antigens on human T lymphocytes and thymocytes. Purified cells were surface-labeled with NaB3H4 after treatment with neuraminidase and galactose oxidase. Immunoprecipitations were performed with rabbit anti-human T cell-specific antibodies using coprecipitation with protein A-containing staphylococci strain Cowan I. The labeled membrane glycoproteins and the precipitates were subjected to polyacrylamide slab gel electrophoresis and visualized by fluorography. The antibodies specifically precipitated 4 proteins called GP 200, GP 180, GP 165 and GP 160 (mol. wts. = 200,000, 180,000, 165,000 and 160,000) from surface-labeled T lymphocytes and low-density (medullary) thymocytes. The GP 200 and GP 180 were not labeled on high-density (cortical) thymocytes. A protein with a mol. wt. of 45,000 was precipitated from thymocytes. Another glycoprotein on T lymphocytes and thymocytes with a mol. wt. similar to that of mouse and rat Thy-1 or theta antigen (mol. wt. 24,000) reacted with the antibodies.
D000818:Animals; D000954:Antigens, Surface / Q000276:immunology*; D000961:Antilymphocyte Serum / Q000276:immunology; D002675:Child, Preschool; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000032:analysis / Q000302:isolation & purification; D006801:Humans; D007519:Isoantigens; D011817:Rabbits; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology*
D000954:Antigens, Surface; D000961:Antilymphocyte Serum; D006023:Glycoproteins; D007519:Isoantigens