ANALYSIS OF COMMITMENT OF HUMAN-LEUKEMIA HL-60 CELLS TO TERMINAL GRANULOCYTIC MATURATION

  • 1 January 1985
    • journal article
    • research article
    • Vol. 45  (5) , 2334-2339
Abstract
Analysis of commitment of human promyelocytic leukemia HL-60 cells to terminal granulocytic maturation induced by dimeyhyl sulfoxide (DMSO) or retinoic acid (RA) was accomplished using biochemical measurements and a plasma clot clonal assay system that permits a high plating efficiency of 40-60%. Commitment to granulocytic maturation occurs very rapidly. When cells were exposed to these inducers for only 8-18 h, an interval much shorter than a single generation time and were then subcultured in inducer-free plasma clots, they demonstrated a decrease in proliferative capacity and form colonies composed of mature nitroblue tetrazolium (NBT)-positive cells along with occasional colonies containing both NBT-positive and NBT-negative cells; in both types of colony, the NBT-positive cells wre widely dispersed. Undifferentiated HL-60 cells gave rise to compact NBT-negative colonies or large size without cell migration. HL-60 cell differentiation induced by either DMSO or RA was associated with a progressive decline in both DNA and RNA synthesis; this inclues transcriptional inactivation of ribosomal DNA sequences. In contrast to DMSO, which induces development primarily of metamyelocytes, RA treatment lead to the accumulation of more mature band and segmented neutrophils; sequential exposure of cells pretreated with DMSO to RA alone failed to cause rapid appearance of segmented neutrophils. It was concluded that HL-60 cells become very rapidly committed to terminal maturation and that DMSO and RA appear to induce granulocytic maturation via 2 different mechanisms.