title: The origin of chicken hematopoietic colonies as assayed in semisolid agar.
abstract: This investigation was undertaken to determine whether primitive stem cells and/or fully differentiated macrophages were the source of in vitro colonies derived from hematopoietic tissues. The chicken colony-forming cell (CFC) present in uncultured yolk sac was a nonadherent, presumably undifferentiated cell. The efficiency of colony formation in this case was approximately 0.08%. In contrast to uncultured yolk sac, the CFC present in one-week old yolk sac cultures was evidently a macrophage. Yolk sac cultures, which consisted of greater than 99% macrophages, produced colonies with an efficiency of 1-5% while cultures derived from peritoneal macrophages produced colonies with an efficiency of 10%. Silica selectively destroyed macrophages and reduced the colony forming efficiency of cells derived from yolk sac cultures.
mesh_terms: D000362:Agar; D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002448:Cell Adhesion; D002452:Cell Count; D002454:Cell Differentiation; D002455:Cell Division; D002469:Cell Separation; D002642:Chick Embryo / Q000166:cytology*; D002999:Clone Cells; D005321:Extraembryonic Membranes; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects; D008747:Methylcellulose; D012822:Silicon Dioxide / Q000494:pharmacology; D014357:Trypsin
chemical_list: D012822:Silicon Dioxide; D000362:Agar; D008747:Methylcellulose; D014357:Trypsin