Synthesis of colony-stimulating factor (CSF) and differentiation-inducing factor (D-factor) by osteoblastic cells, clone MC3T3-E1.
The role of osteoblasts in inducing the proliferation and differentiation of bone marrow cells was examined. Conditioned medium obtained from mouse osteoblastic cell (MC3T3-E1) cultures stimulated colony formation of mouse bone marrow cells (CSF) and differentiation of mouse myeloid leukemia cells (M1) into macrophage-like cells (D-factor). The CSF activity increased time dependently in parallel with the increase of alkaline phosphatase activity during the culturing of the MC3T3-E1 cells. The activity of the D-factor attained a maximum on days 12 - 15 and decreased thereafter. Both the CSF and the D-factor were eluted in a range of 25,000 to 67,000 daltons on gel filtration. The fraction containing both factors exhibited bone-resorbing activity. These results suggest that osteoblasts are involved in bone resorption at least in part by enhancing the proliferation and differentiation of osteoclast progenitors.
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001853:Bone Marrow / Q000187:drug effects; D001854:Bone Marrow Cells; D001862:Bone Resorption / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D006023:Glycoproteins / Q000096:biosynthesis*; D006131:Growth Inhibitors; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism; D008222:Lymphokines; D008433:Mathematics; D051379:Mice; D008810:Mice, Inbred C57BL; D010006:Osteoblasts / Q000378:metabolism*; D013997:Time Factors
D003115:Colony-Stimulating Factors; D006023:Glycoproteins; D006131:Growth Inhibitors; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D008222:Lymphokines; D000469:Alkaline Phosphatase