title: High-level expression of the ER-MP58 antigen on mouse bone marrow hematopoietic progenitor cells marks commitment to the myeloid lineage.
abstract: Studies on the early events in the differentiation of the nonspecific immune system require the identification and isolation of myeloid-committed progenitor cells. Using the monoclonal antibodies (mAb) ER-MP12 and ER-MP20, generated against immortalized macrophage precursors, we have shown previously that the earliest macrophage colony-stimulating factor (M-CSF)-responsive cells in the bone marrow have the ER-MP12hi 20- phenotype. In addition, we found that the ER-MP12hi 20- subset (comprising about 2 % of total nucleated marrow) contains progenitor cells of all hematopoietic lineages. Aiming at the identification and purification of the myeloid progenitor cells within the ER-MP12hi 20-subset, we used ER-MP58, a marker expressed at high level by all M-CSF-responsive bone marrow progenitors. With this marker the ER-MP12hi 20- cell population could be divided into three subfractions: one with absent or low level ER-MP58 expression, one with intermediate, and one with high ER-MP58 expression. These subfractions were isolated by fluorescence-activated cell sorting and tested in vitro and in vivo for their differentiation capacities. In addition, the expression of ER-MP58 on stem cell subsets was examined in the cobblestone area-forming cell (CAFC) assay. Our data indicate that in the ER-MP12hi 20- subpopulation myeloid-committed progenitors are characterized by high-level expression of the ER-MP58 antigen, whereas cells with other or broader differentiation capacities have an ER-MP58 negative/low or intermediate phenotype. These myeloid-committed progenitors have no significant repopulating ability in vivo, in contrast to the ER-MP58 intermediate cells. Primitive CAFC-28/35, corresponding to cells providing long-term hematopoietic engraftment in vivo, also did not express the ER-MP58 Ag at a high level. Thus, cells committed to the myeloid lineage can be separated from progenitor cells with other differentiation capacities by means of multiparameter cell sorting using ER-MP58 in combination with ER-MP12 and ER-MP20.
authors.affiliation: Department of Immunology, Erasmus University, Rotterdam, The Netherlands. debruijn@CH1.fgg.eur.nl
authors.forename: M F
authors.initials: MF
authors.lastname: de Bruijn
authors.forename: R E
authors.initials: RE
authors.lastname: Ploemacher
authors.forename: A E
authors.initials: AE
authors.lastname: Mayen
authors.forename: J S
authors.initials: JS
authors.lastname: Voerman
authors.forename: W A
authors.initials: WA
authors.lastname: Slieker
authors.forename: W
authors.initials: W
authors.lastname: van Ewijk
authors.forename: P J
authors.initials: PJ
authors.lastname: Leenen
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000096:biosynthesis* / Q000276:immunology; D001853:Bone Marrow / Q000378:metabolism*; D001854:Bone Marrow Cells; D002454:Cell Differentiation / Q000502:physiology; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D016173:Macrophage Colony-Stimulating Factor / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013950:Thymus Gland / Q000166:cytology / Q000254:growth & development
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D016173:Macrophage Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor