Induction of Differentiation of Cultured Human and Mouse Myeloid Leukemia Cells by Alkyl-lysophospholipids1

Alkyl-lysophospholipids are synthetic analogs of naturally occurring lysophospholipids. The effects of these compounds on cell proliferation and differentiation of cultured human (HL60) and mouse (M1) myeloid leukemia cells were studied. Both cell lines were induced to differentiate into morpholog ically and functionally mature granulocytes and macrophages by incubation with a wide variety of these compounds. Some alkyl-lysophospholipids induced differentiation (judged mor phologically and by the appearance of abilities to reduce nitro blue tetrazolium, to phagocytize latex particles, and to induce lysozyme activity) of both the cell lines at concentrations of 1 jug/ml. However, these compounds did not affect colony for mation of normal mouse bone marrow cells even at a higher concentration, 20 (¿g/ml. These results suggest that alkyllysophospholipids induce cell differentiation of myeloid leuke mia cells without affecting proliferation and differentiation of normal bone marrow cells. Thus, these compounds could be useful in therapy of myeloid leukemia.