DIFFERENTIAL EXPRESSION OF QA-M2 ALLOANTIGEN ON MURINE HEMATOPOIETIC PROGENITOR CELLS - SELECTIVE ENRICHMENT FOR MEGAKARYOCYTE PROGENITORS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 11  (6) , 527-541
Abstract
The selective expression of Qa-m2 antigen on murine megakaryocyte colony-forming cells (MEG-CFC) was demonstrated. A monoclonal antibody defining the Qa-m2 alloantigen inhibited in the presence of complement [C], in vitro formation by murine bone marrow cells of megakaryocyte colonies, but not granulocyte-macrophage, erythroid or eosinophil colonies. Inhibition of megakaryocyte colony formation was shown, by mixing and other experiments, to be due to C-mediated lysis of MEG-CFC rather than lysis of accessory cells. B lymphocyte colony formation was reproducibly decreased by .apprx. 50%, demonstrating the presence of Qa-m2+ and Qa-m2- subsets of B lymphocyte colony-forming cells. MEG-CFC and granulocyte-macrophage colony-forming cells (GM-CFC) were Thy-1-, Ly-1-, Ly-6- and Ly-5-. Fractionation of Thy-1-, Ig- marrow by rosetting Qa-m2+ cells and centrifuging them through an Isopaque-Ficoll gradient yielded up to 8-fold enrichment for MEG-CFC and > 20-fold separation of MEG-CFC from GM-CFC. The anti-Qa-m2 antibody should be useful for further purification of MEG-CFC, and investigation of hemopoietic differentiation.