HUMAN MYELOID PRECURSORS FORMING COLONIES IN DIFFUSION-CHAMBERS EXPRESSES THE IA-LIKE ANTIGEN

  • 1 January 1979
    • journal article
    • research article
    • Vol. 54  (5) , 1188-1191
Abstract
Normal human bone marrow contains cells capable of forming myeloid colonies (CFU-DG) in fibrin clots in diffusion chambers placed in the peritoneal cavity of cyclophosphamide-treated mice. Evidence accumulated indicating that these colony-forming cells represent an earlier stem cell than the granulocyte-monocyte precursor cell (CFU-C) assayed in soft agar. These stem cells expressed the Ia-like or DR antigen. In the presence of rabbit Ia antiserum at a titer of 1:300, all CFU-DG were inhibited. Cytotoxicity was complement-dependent. The megakaryocyte stem cell apparently also expresses the Ia antigen.