title: Microinjection of macromolecules into leukemic cells by cell fusion technique: search for intracellular growth-suppressive factors.
abstract: To investigate the intracellular molecular events during leukemic cell proliferation, we have examined the method of ghost-mediated microinjection of macromolecules into leukemic cell line cells (HL-60). Samples were packed into red cell ghosts. Microinjection was performed by the fusion of ghosts and HL-60 cells using the hemagglutinating virus of Japan (HVJ). Fusion rate was about 80-90%, when determined by the injection of FITC-labeled globulins (IgG) or diphtheria toxin fragment A into HL-60 cells. When the nuclear protein extract from normal granulocytes was injected into HL-60 cells, their growth was significantly suppressed. The injection of the nuclear protein extract from HL-60 itself into HL-60 cells did not inhibit their growth. This finding suggests that leukemic cells may be deficient in intracellular regulatory factors which have suppressive activity on cell growth.
mesh_terms: D000818:Animals; D002459:Cell Fusion; D004910:Erythrocyte Membrane; D006131:Growth Inhibitors / Q000008:administration & dosage; D006801:Humans; D007074:Immunoglobulin G / Q000008:administration & dosage; D007942:Leukemia, Experimental / Q000188:drug therapy / Q000473:pathology*; D008845:Microinjections / Q000379:methods*; D009698:Nucleoproteins / Q000008:administration & dosage
chemical_list: D006131:Growth Inhibitors; D007074:Immunoglobulin G; D009698:Nucleoproteins