INHIBITOR OF HEMATOPOIETIC CELL-PROLIFERATION DERIVED FROM A HUMAN LEUKEMIC CELL LINE

  • 1 January 1978
    • journal article
    • research article
    • Vol. 52  (1) , 143-152
Abstract
A continuously growing human myeloid leukemia cell line (K562) produced a potent high molecular weight inhibitor of hematopoietic cell proliferation. It was most active against myeloid stem cells (CFU-C) and proliferating T [thymus-derived] lymphocytes. It was less active against erythroid precursors (CFU-E) and did not inhibit fibroblasts or established lines of epithelioid cells or B [bone marrow-derived] lymphocytes. Inhibition of CFU-C was by direct interaction rather than modulation of production of colony-stimulating activity and probably occurred at restricted points in the cell cycle. Inhibition could, within limits, be reversed by washing the target cells. Production of inhibitors of hematopoiesis is not a general property of established cell lines and only 2 were identified in screening of 30 such lines.