In vitro evaluation of a bone morphogenetic protein-2 nanometer hydroxyapatite collagen scaffold for bone regeneration

Scaffold fabrication and biocompatibility are crucial for successful bone tissue engineering. Nanometer hydroxyapatite (nHAP) combined with collagen (COL) is frequently utilized as a suitable osseous scaffold material. Furthermore, growth factors, including bone morphogenetic protein‑2 (BMP‑2), are used to enhance the scaffold properties. The present study used blending and freeze‑drying methods to develop a BMP‑2‑nHAP‑COL scaffold. An ELISA was performed to determine the BMP‑2 release rate from the scaffold. Flow cytometry was used to identify rat bone marrow‑derived mesenchymal stem cells (BMSCs) prior to their combination with the scaffold. Scanning electron microscopy was used to observe the scaffold structure and BMSC morphology following seeding onto the scaffold. BMSCs were also used to assess the biological compatibility of the scaffold in vitro. BMP‑2‑nHAP‑COL and nHAP‑COL scaffolds were assessed alongside the appropriate control groups. Cells were counted to determine early cell adhesion. Cell Counting kit‑8 and alkaline phosphatase assays were used to detect cell proliferation and differentiation, respectively. Gross morphology confirmed that the BMP‑2‑nHAP‑COL scaffold microstructure conformed to the optimal characteristics of a bone tissue engineering scaffold. Furthermore, the BMP‑2‑nHAP‑COL scaffold exhibited no biological toxicity and was demonstrated to promote BMSC adhesion, proliferation and differentiation. The BMP‑2‑nHAP‑COL scaffold had good biocompatibility in vitro, and may therefore be modified further to construct an optimized scaffold for future bone tissue engineering.