Macrophage Colony Stimulating Factor (M-CSF) is a 18.54 kDa member of hematopoietic Growth Factors with 159 amino acid residues. M-CSF produced by osteoblasts and osteoblast precursors. M-CSF stimulates the growth and differentiation of the monocyte lineage, and promotes the survival, proliferation, and functions of mature monocytes/macrophages.