Synergistic Effects of SDF-1 and BMP-2 Delivery from Proteolytically Degradable Hyaluronic Acid Hydrogels for Bone Repair

In order to achieve bone repair, bone morphogenetic protein-2 (BMP-2) is typically delivered in non-physiological doses and can result in significant adverse side effects. To reduce the amount of BMP-2 necessary for bone formation, we delivered a known chemokine (stromal cell derived factor-1, SDF-1) in combination with BMP-2 using proteolytically degradable hydrogels. A critical-sized calvarial defect was used to determine the effect of biomolecule delivery on bone formation in vivo. The treatment group with combined SDF-1 and BMP-2 hydrogel delivery showed significantly higher bone formation when compared to hydrogels loaded with the same BMP-2 or SDF-1 concentrations alone, suggesting the combined delivery of both biomolecules synergistically improves osteogenesis.