Local delivery of recombinant human bone morphogenic protein-2 (rhBMP-2) from rhBMP-2/heparin complex fixed to a chitosan scaffold enhances osteoblast behavior

Abstract

The objective of this study was to determine the effects on osteoblast activity of a recombinant human bone morphogenic protein (rhBMP)-2/heparin complex immobilized on a chitosan scaffold (Hep-C-rhBMP-2/chitosan) compared to a rhBMP-2-dipping chitosan (rhBMP-2/chitosan) and to a chitosan scaffold alone. Scanning electron microscopy (SEM) confirmed that the surface and cross morphologies of Hep-C-rhBMP-2/chitosan and rhBMP-2/chitosan were similar to those of the chitosan scaffold, and that the Hep-C-rhBMP-2/chitosan scaffold achieved sustained, controlled release of rhBMP-2 compared to the rhBMP-2/chitosan scaffold. We used measurements of alkaline phosphatase activity, calcium deposition, and real-time PCR to determine that significantly more MG-63 cells were successfully cultured on Hep-C-rhBMP-2/chitosan than on rhBMP-2/chitosan or the chitosan scaffold alone. These results suggest that the Hep-C-rhBMP-2/chitosan scaffold promotes osteoblast behavior beyond the other two scaffolds tested. This system may have advantages for dental and orthopedic applications to regenerate bone.