COMPARATIVE-ANALYSIS OF THE EFFECTS OF RECOMBINANT CYTOKINES ON THE GROWTH AND DIFFERENTIATION OF ML-1, A HUMAN MYELOGENOUS LEUKEMIC-CELL LINE

We have investigated the effect of a number of cytokines on the human acute myelomonocytic leukemic cell line, ML-1. The differentiation ind ucing effects of interleukins (IL-1 beta, IL-3 and IL-6), colony stimu lating factors (GCSF and GMCSF), TNF, LIF and IFNg, were studied eithe r individually or in combination. Criteria for monocytic differentiati on were as follows: an increase in the percentage of cells reducing ni troblue tetrazolium (NBT) salt, an increase in the alkaline phosphatas e activity as well as the appearance of macrophagic phenotype. Among a ll the cytokines tested, only TNF was found to induce differentiation and to inhibit growth of ML-1 cells. IL-3, IL-6, interferon gamma, GCS F and to a smaller extent IL-1 beta and GMCSF synergized the different iation inducing activity of TNF.