Recloned Colonies Positive for T-Cell-Associated Antigens Derived from Mixed Hemopoietic Colonies (CFU-GEMM) 1

Abstract

Abstract

Human pluripotent hemopoietic progenitors (CFU-GEMM) can be identified by their ability to form colonies in culture that contain granulocytes, erythroblasts, macrophages, and megakaryocytes. Forty-six individual mixed colonies from four individuals were prepared by cytocentrifugation and examined for cells positive for human T-cell markers using the monoclonal antibodies E 2-22 and OKT 3 and fluorescently labeled goat F(ab')₂ anti-mouse IgG antibody. Sixteen primary mixed colonies were found to be positive for the monoclonal antibodies E 2-22 and OKT 3. Seventy-nine primary mixed colonies derived from these four individuals were aspirated, dispersed, and then recloned. Twenty-three primary mixed colonies formed 97 secondary hemopoietic colonies. All cells in 50 recloned hemopoietic colonies were positive for the antibodies directed against T cells.