Stromal Cell-Derived Factor-1 (SDF-1) Recruits Osteoclast Precursors by Inducing Chemotaxis, Matrix Metalloproteinase-9 (MMP-9) Activity, and Collagen Transmigration

Abstract

SDF-1, a chemokine highly expressed by bone vascular endothelial and marrow stromal cells, may be a key signal for the selective attraction of circulating OC precursors into bone and their migration within marrow to appropriate perivascular stromal sites for RANKL differentiation into resorptive OCs. Thus, SDF-1 and RANKL likely serve complementary physiological functions, partly mediated through increases in MMP-9, to coordinate stages of OC precursor recruitment, development, and function.