Lee DH, Park BJ, Lee M, Lee JW, Kim JK, Yang H, Park J. Chemotactic Migration of Human Mesenchymal Stem Cells and MC3T3-E1 Osteoblast-Like Cells Induced by COS-7 Cell Line Expressing rhBMP-7. Tissue Engineering. 2006 Jun 22;0(0):060706073730022. doi: 10.1089/ten.2006.12.ft-141.