Chemotaxis of muscle-derived mesenchymal cells to bone-inductive proteins of rat

In this investigation we examined the chemotaxis of muscle-derived mesenchymal cells from neonatal rats to partially purified extracts of demineralized bone matrix with osteoinductive properties. Using the modified Boyden chamber assay and muscle-derived mesenchymal cells obtained from neonatal Long-Evans rats, we tested the chemotactic properties of the 4 M guanidine-HCl extract from demineralized rat bone matrix and fractions thereof that were derived from sequential Sepharose CL-6B, TSK-3000 and HPLC-C18 chromatography. We have identified that those fractions exhibiting chemotactic properties were also osteoinductive. Therefore, demineralized bone matrix serves as its own soluble signal and insoluble substratum in the inductive process leading to endochondral bone formation in vivo.