Biochemical events accompanying macrophage activation and the inhibition of colony‐stimulating factor‐1‐induced macrophage proliferation by tumor necrosis factor‐α, interferon‐γ, and lipopolysaccharide

Abstract

Agents that can arrest cellular proliferation are now providing insights into mechanisms of growth factor action and how this action may be controlled. It is shown here that the macrophage activating agents tumor necrosis factor‐α (TNFα), interferon‐γ (IFNγ), and lipopolysaccharide (LPS) can maximally inhibit colony stimulating factor‐1 (CSF‐1)‐induced, murine bone marrow‐derived macroohage (BMM) DNA synthesis even when added 8–12 h after the growth factor, a period coinciding with the G1/S‐phase border of the BMM cell cycle. This inhibition was independent of autocrine PGE2 production or increased cAMP levels. In order to compare the mode of action of these agents, their effects on a number..