title: An antigenic difference between cells forming early and late haematopoietic spleen colonies (CFU-S).
abstract: Murine pluripotent haematopoietic stem cells have generally been assayed by their ability to form macroscopic colonies of haematopoietic cells in the spleens of heavily irradiated recipient mice (colony-forming unit-spleen or CFU-S assay). However, recent evidence suggests that there are distinct subpopulations of CFU-S. Most spleen colonies present 7-8 days after injection consist of differentiated erythroid cells, contain no primitive myeloid or erythroid precursor cells and disappear from the spleen within 3 days, whereas the majority of colonies present at 10-12 days contain primitive precursors, are multilineal and cannot be detected at 7-8 days. Furthermore, many 10-day-old spleen colonies do not contain cells capable of forming spleen colonies in secondary irradiated recipients (an index of the self-renewal capacity of stem cells) whereas at day 14 almost all colonies contain these CFU-S. These studies suggest that only when colonies are scored at or later than 11-12 days is the spleen colony technique adequate for the assay of multipotential stem cells. We now report an antigenic difference between subpopulations of CFU-S forming early (day 8) and late (day 14) spleen colonies which has been used to purify multipotential haematopoietic stem cells from murine bone marrow.
mesh_terms: D000367:Age Factors; D000818:Animals; D000954:Antigens, Surface / Q000032:analysis*; D002454:Cell Differentiation; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology*; D015395:Histocompatibility Antigens Class I; D051379:Mice; D013154:Spleen / Q000166:cytology / Q000276:immunology*
chemical_list: D000954:Antigens, Surface; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens