title: Use of cloned populations of mouse lymphocytes to analyze cellular differentiation.
abstract: We describe a method for generation of homogeneous cell populations that each arise from clonal expansion of cells at a discrete stage of differentiation within a single lineage. We have used this to produce continuously propagatable lymphocyte clones. Each clone represents a cell at a progressive stage of thymus-dependent cellular differentiation. These cloned cells bear stable surface membrane glycoproteins characteristic of precursor cells and mature progeny; conditions allowing maximal cloning efficiencies for each cell type (10-85%) have been established. Mature lymphocyte clones continue to express specialized function and provide material for biochemical analysis of T lymphocyte functions; one fully differentiated clone from the "inducer" lymphocyte set synthesizes a molecule that activates other lymphocytes to secrete immunoglobulin. This activity is associated with a highly purified molecule having a molecular weight of 45,000 daltons and an isoelectric point of approximately 6.0. This molecule, together with clones of precursor and mature T lymphocytes, may provide a system to further study the mechanisms of gene activation during cellular differentiation.
mesh_terms: D000954:Antigens, Surface / Q000032:analysis; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D002478:Cells, Cultured; D002999:Clone Cells / Q000166:cytology*; D003602:Cytotoxicity, Immunologic; D008099:Liver / Q000166:cytology / Q000196:embryology; D008222:Lymphokines / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology
chemical_list: D000954:Antigens, Surface; D008222:Lymphokines