title: Suiciding of lymphocytic precursor cells by tritiated nucleosides, in vitro.
abstract: Differences in suiciding by various tritiated nucleosides were observed between two functional assays for in vitro lymphocytic precursor cell development, the hemolysin plaque-forming cell (PFC) assay and the B lymphocytic colony-forming cell (CFC-L) assay, using BDF1 mouse spleen cells. PFC growth was markedly reduced by an early (days 0-1) pulse of tritiated deoxyadenosine ([3H]dAdo), but relatively unaffected by a pulse of tritiated thymidine ([3H]dThd) during the same interval. In contrast, CFC-L formation significantly dropped after an early (day 0) [3H]dThd pulse, as well as after pulses of [3H]dAdo and the corresponding tritiated ribosides, uridine and adenosine. This implied a cycling state in an early lymphocytic precursor cell, as opposed to the PFC insensitivity to an early [3H]dThd pulse. The response pattern of colonies and clusters to [3H]dThd supported our notion of a delayed suiciding of CFC contributing to the increase in cluster numbers.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005260:Female; D006462:Hemolytic Plaque Technique; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009705:Nucleosides / Q000378:metabolism*; D013997:Time Factors; D014316:Tritium
chemical_list: D009705:Nucleosides; D014316:Tritium