Novel bone repairing scaffold consisting of bone morphogenetic Protein-2 and human Beta Defensin-3

Synthetic biomaterials assist in modulating the vascular response in an injured bone by serving as delivery vehicles of pro-angiogenic molecules to the site of injury or by serving as mimetic platforms which offer support to cell growth and proliferation.

This study applied natural phospholipid modified protein technologies together with low temperature three-dimensional printing technology to develop a new model of three-dimensional artificial bone scaffold for potential use in repairing body injuries. The focus was to create a porous structure (PS) scaffold of two components, Bone Morphogenetic Protein-2 and Human Beta Defensin-3 (BMP2 and hBD3), which can synchronously realize directional bone induction, angiogenesis and postoperative antibacterial effects. BMP2 induces osteogenesis, whereas hBD3 is antibacterial.

Our data showed that in the BMP2-hBD3-PS or hBD3-PS scaffolds, BMP2 had a slow-release rate of about 40% in 30 days, ensuring that BMP2 could penetrate into stem cells for osteogenic differentiation for a long time. The scaffolds promoted cell growth when in combination with BMP2, thus showing its importance in promoting cell growth. Alkaline Phosphatase (ALP) staining showed that the ALP content of BMP2-hBD3-PS and BMP2-PS had a significant increase in samples that contained BMP2, thus showing that these scaffolds promoted osteogenic differentiation. In all the constructs that had hBD3, they displayed antibacterial properties with hBD3, having a slow release of about 35% in 30 days, thus ensuring they provided protection.

Based on this study, the 3D printed BMP2 scaffolds show a great potential for the development of biodegradable bone implants.

Level II, experimental comparative design.