M-CSF, Human, Recombinant

Macrophage Colony-Stimulating Factor (M-CSF or CSF-1) can be produced by several types of cells including (but not limited to) fibroblasts, activated macrophages and bone marrow stromal cells. Some of the roles of M-CSF include stimulation of the formation of macrophage colonies from bone marrow hematopoietic progenitor cells, induction of proliferation of isolated macrophages, enhancement of macrophage antibody-dependent cell-mediated cytotoxicity etc. M-CSF is synthesized as a membrane-bound propeptide and it can exist either as a secreted, soluble form or as a membrane-anchored form, both of which are biologically active. Natural M-CSFs are glycosylated, disulfide-linked homodimeric proteins with molecular weights ranging from 40-70 kDa. Several C-terminal variants of the soluble form of M-CSF have been found. The N-terminal 150 amino acid residues of the mature M-CSF, a region necessary and sufficient for interaction with the M-CSF receptor, is highly conserved (80% homology) between the human and murine proteins. Human M-CSF is active in the murine system, but murine M-CSF is species-specific. M-CSF is a glycoprotein, but the carbohydrate moiety is not necessary for biological activity.