Use macrophage colony-stimulating factor (M-CSF) to regulate the proliferation and differentiation of myeloid hematopoietic progenitor cells to mononuclear phagocytic cell lineages, including monocytes, macrophages, and osteoclasts. M-CSF is a homodimeric glycoprotein growth factor that is crucial to the development of tissue-resident macrophages in most tissues (Ginhoux & Jung Nat Rev Immunol, 2014) and regulates inflammatory responses together with other stimuli such as IFN-γ, LPS, and IL-4 (Murray et al. Immunity, 2014). M-CSF exerts its biological effects by signaling through a receptor tyrosine kinase (CSF-1R or M-CSF-R) (Hamilton JA J Leukoc Biol, 1997). Stimulation of the CSF-1R upon binding to M-CSF activates MAPK, PI3K, and PLCγ signaling pathways (Chockalingam & Ghosh Tumour Biol, 2014). Mouse recombinant M-CSF from STEMCELL comes lyophilized with ≥ 95% purity; EC50 ≤ 10 ng/mL; endotoxin levels verified ≤ 1 EU/μg protein. Alternative names: Colony stimulating factor 1, CSF-1.