title: Conditioned medium from plateau-phase cells. Effect on growth of proliferative cells and on repair of potentially lethal radiation damage.
abstract: In vitro cell cultures grown into plateau phase may be more suitable than exponentially growing cells as a model for tumor cell growth in vivo. Conditioned medium extracted from cells in plateau phase inhibits growth of log-phase cultures of either the same or a different cell line. Attempts to demonstrate that this inhibition is due to a heat-labile diffusible substance have failed. Conditioned medium extracted from plateau-phase cultures was effective in enhancing repair of potentially lethal damage following x irradiation. Cell survival is significantly increased following a six-hour postirradiation culture in conditioned medium as opposed to complete fresh medium.
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular; D002455:Cell Division; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured / Q000378:metabolism / Q000528:radiation effects*; D006224:Cricetinae; D003470:Culture Media; D004307:Dose-Response Relationship, Radiation; D008113:Liver Neoplasms; D008168:Lung; D009374:Neoplasms, Experimental / Q000473:pathology* / Q000532:radiotherapy; D051381:Rats
chemical_list: D003470:Culture Media