title: Cytotoxic and fluorescent assays for thymocyte subpopulations differing in surface thy-1 level.
abstract: A number of analytical techniques for distinguishing and separating the "high theta" "low theta" subpopulations of mouse thymocytes have been compared. A differential cytotoxic assay was compared to a quantitative immunofluorescent assay on individual cells using flow cytofluorometry and cell sorting. Conventional anti-Thy-1 antisera were compared with a monoclonal IgM anti-Thy-1. The monoclonal reagent greatly improved both types of assay, eliminated a number of artifacts and allowed either procedure to be used to give a clear distinction, based on Thy-1 level, between the two subpopulations. The distribution of Thy-1 on thymocytes is bimodal, rather than continuous. These separate "high theta" and "low theta" categories each includes a population a population of dividing cells.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis*; D000961:Antilymphocyte Serum; D003601:Cytotoxicity Tests, Immunologic; D005260:Female; D005455:Fluorescent Antibody Technique; D007075:Immunoglobulin M; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*
chemical_list: D000954:Antigens, Surface; D000961:Antilymphocyte Serum; D007075:Immunoglobulin M