title: Studies on thymocyte subpopulations in guinea pigs. V. Rosette formation as a tool to separate thymocyte growth factor responsive and mitogen reactive cells.
abstract: 78% of guinea pig thymocytes formed rosettes after 1 h incubation with rabbit erythrocytes. They were separated from nonrosetting cells by layering over a Percoll solution and centrifugation. The nonrosetting cells (RE-) contained a large proportion of spontaneously DNA synthesizing cells as well as cells able to cooperate in a proliferative response to the mitogenic lectins concanavalin A and phytohemagglutinin. In contrast, cells which responded to a thymocyte growth factor were rosette forming (RE+). Proliferating thymus cells were earlier shown to reside in a low density population called Ia. Here we show that, whereas both RE+ and RE- cells of population Ia contain proliferating cells, only the RE+ respond to the growth factor. Thus, the formation of 'early' rosettes can form the basis for enrichment of thymocyte growth factor responsive cells and the simultaneous separation of these from mitogen reactive cells.
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D003208:Concanavalin A / Q000276:immunology; D004247:DNA / Q000096:biosynthesis; D004912:Erythrocytes / Q000276:immunology; D006133:Growth Substances / Q000276:immunology*; D006168:Guinea Pigs / Q000276:immunology*; D008213:Lymphocyte Activation; D008934:Mitogens / Q000276:immunology; D010835:Phytohemagglutinins / Q000276:immunology; D011817:Rabbits / Q000276:immunology; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000145:classification*; D013950:Thymus Gland / Q000166:cytology
chemical_list: D006133:Growth Substances; D008934:Mitogens; D010835:Phytohemagglutinins; D003208:Concanavalin A; D004247:DNA