The biologic effects of macrophage colony-stimulating factorson osteoclastic cells in vitro

Objective To investigate the biologic effects of macrophage colony-stimulating factor(M、CSF) on osteoclastic cells during the bone metabolism in vitro.Methods The bone marrow cells of mice were treated with different concentration of M、CSF and RANKL in vitro.The mice stromal cells were cultured and osteoclast was supported with or without bone slice.TRAP positive multinuclear cells were measured by tartrate-resistant acid phosphatase (TRAP) staining and the function of osteoclast was detected by pit staining.Results The range of limiting M、CSF concentrations,the number of TRAP-positive multinuclear cells increased significantly depending on the M-CSF doses(r=0.7504,P0.05),and the pit numbers increased significantly depending on the M、CSF doses(r=0.9365,P≤0.0001). Without M、CSF or RANKL,the number of TRAP-positive multinuclear cells had no change (P=0.0191). Conclusions The proliferation,differentiation and survival of osteoclast is regulated by M、CSF and RANKL. M、CSF is critically involved in the differentiation of osteoclast and it can promote the osteoclast to resorpt the bone.One of the major function of M、CSF for bone metabolism is upregulation osteoclast system.