Effect of silk RGD fusion protein modified hydroxyapatite/silk fibroin scaffolds on the growth of osteoblasts

A bombyx mori silk fibroin-RGD fusion protein was used to modify the porous hydroxyapatite/silk fibroin(HA/SF) composite scaffolds by soaking the scaffolds into the protein solution with different concentrations. The osteoblasts, MG-63 and MC3T3-E1 were seeded onto the silk-RGD modified HA/SF composite scaffolds in order to evaluate the cell adhesion, proliferation and differentiation on scaffolds. The results show that the cell adhesion property in the silk-RGD modified scaffolds is higher than that in the control (i.e., unmodified scaffolds), and depended on the concentration of silk-RGD. After being cultured for 7 d in vitro, the proliferation rates of MG-63 and MC3T3-E1 cells increase by 21% and 50%, respectively, compared with the control. For MC3T3-E1 cells, the alkaline phosphatase (ALP) activity data show an improvement of cell differentiation on the scaffolds after the silk-RGD modification, but no significant difference is found for the MG-63 cells.