Dual delivery of bone morphogenetic protein‑2 and basic fibroblast growth factor from nanohydroxyapatite/collagen for bone tissue engineering

Abstract

Background: In bone tissue engineering, the fabrication and biocompatibility of scaffold are crucial. Among many scaffold materials, nanohydroxyapatite (nHAP) and collagen (COL) are chosen as building materials of scaffold. At the same time, growth factors were also used to modify the scaffolds. Methods: In this study, blending and freeze drying methods were adopted together in order to build basic fibroblast growth factor (bFGF)-bone morphogenetic protein-2 (BMP-2)-nHAP/COL scaffolds. ELISA was applied to test the release of bFGF and BMP-2 on the scaffold. The flow cytometry was used to identify bone marrow mesenchymal stem cells (BMSCs). Scanning electron microscope was adopted to observe scaffolds and cells morphology. BMSCs were seeded on the scaffolds to test the biological compatibility in vitro. Cells were counted to detect early cell adhesion. Cell counting kit-8 assay was adopted to detect cell proliferation and alkalinephosphatase assay was applied to detect cell activity. Results: The characterization of bFGF-BMP-2-nHAP/COL scaffolds meets the requirements of ideal bone tissue engineering scaffolds. BMSCs that were isolated, purified and passaged satisfied the needs of further experiments. The growth status of cells on bFGF-BMP-2-nHAP/COL scaffolds was satisfactory. Cell adhesion was the highest in the bFGF-BMP-2-nHAP/COL scaffolds group. The cell viability and ALP activity of bFGF-BMP-2-nHAP/COL scaffolds group were the highest. Conclusion: Taken together, bFGF-BMP-2-nHAP/COL scaffolds have good biocompatibility in vitro and promote adhesion, proliferation, differentiation of BMSCs.