title: Lymphocyte differentiation in the rabbit thymus.
abstract: Density separation of rabbit thymus lymphoid cells on a continuous and linear Ficoll-Metrizoate gradient resulted in the appearance of three subpopulations of lymphoid cells with peak fractions at densities of approx. 1.067, 1.077 and 1.084 g/ml. The subpopulation of the lowest density appeared to consist of cortisone-resistant cells of various size classes, all characterized by a relative low nucleo-cytoplasmic ratio. Glycerol-induced redistribution of particles within the plasma membrane (IMP) of the lymphoid cells, as revealed with the freeze-fracture technique, was present in the subpopulation of lowest density as well as in thymus lymphoid cells of cortisone-treated rabbits in a high percentage of the cells, and present in a very small percentage of the cells of highest density. It is concluded that an increase in the mobility of plasma membrane components may be a significant feature of T-cell education in the rabbit thymus.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002462:Cell Membrane / Q000648:ultrastructure; D002467:Cell Nucleus / Q000648:ultrastructure; D002469:Cell Separation; D005614:Freeze Fracturing; D005990:Glycerol / Q000494:pharmacology; D006854:Hydrocortisone / Q000494:pharmacology*; D008214:Lymphocytes / Q000166:cytology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D011817:Rabbits; D013950:Thymus Gland / Q000166:cytology*
chemical_list: D005990:Glycerol; D006854:Hydrocortisone