Inductive effect of recombinant human interleukin‐1 α and β on differentiation of macrophage‐like tumor cell line P388D1

Abstract
We used the mouse monocyte/macrophage-like tumor cell line P388D1 to test whether or not interleukin-1 (IL-1) stimulates differentiation of monocyte/macrophage progenitors. Incubation of these cells with recombinant human interleukin-1 (rhIL-1) α and β resulted in their increased adherence, stimulation of nonspecific esterase activity, and increased Fc rosette formation. rhIL-1s inhibited cell growth and stimulated Fc rosette formation in a dose-dependent fashion. The cell growth inhibition due to rhIL-1s depended on the concentration of serum in culture medium. Synergism between rhIL-1 and calcium ionophore A23187 was found for the cell growth inhibition and Fc rosette formation. The presence of ethylene glycol bis- (β-aminoethyl ether) N,N,N,N-tetraacetic acid(EGTA) in the medium abolished the stimulatory effect of rhIL-1 on Fc rosette formation of the cell line. These results demonstrate that rhIL-1s are a potent inducer of the differentiation of the macrophage-like tumor cell line P388D1.