Chemotactic Peptides but not Macrophage Colony Stimulating Factor Effect the Synthesis of Inositol Lipids in Macrophages

Abstract Normal bone marrow derived macrophages display a wide variety of biological responses to a number of distinct agonists, for example, Macrophage Colony Stimulating Factor (M-CSF) and chemotactic peptides (such as FMLP). FMLP stimulates reactive oxygen intermediate production in these cells, whilst M-CSF stimulates DNA synthesis. We have compared the effects of these two agents on the production of novel inositol lipids in macrophages. Evidence is presented that FMLP, but not M-CSF elevate the levels of a lipid putatively identified as phosphatidylinositol-3,4-bisphosphate. The implications of this observation on the proposed role of novel inositol lipids in macrophage proliferation are discussed.