Effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the proliferation of granulocyte-macrophage colony-forming cells

Abstract

It has been suggested that 12-O-tetradecanoylphorbol-13-acetate (TPA) may stimulate the proliferation of granulocyte-macrophage (GM) colony-forming cells (CFC) via the GM colony-stimulating factor (CSF) receptor. GM-CFC in unfractionated mouse bone marrow and light density fetal liver (LDFL) cells were induced by TPA to form colonies in the absence of exogenously added GM-CSF. The colonies induced by TPA (10-8 M) were smaller than normally seen with maximal concentrations of GM-CSF, and less than 30% of the GM-CFC formed colonies in the presence of TPA. The number of colonies stimulated by TPA in the absence of GM-CSF was dependent on the number of cells plated. When fewer than 10,000 bone m..