Description: Human Macrophage Colony Stimulating Factor (M-CSF, also called CSF-1) is a ~36 kDa disulfide-linked homodimer produced by a variety of cells including fibroblasts, macrophages, bone marrow stromal cells and endothelial cells. M-CSF regulates macrophage survival, proliferation and differentiation. M-CSF also enhances macrophage killing of tumor cells and microorganisms and regulates cytokine production from macrophages.