A 3D-printed PLGA/HA composite scaffold modified with fusion peptides to enhance its antibacterial, osteogenic and angiogenic properties in bone defect repair

Scaffold materials, seed cells and growth factors are referred to as the three elements of bone tissue engineering (BTE). However, the physical properties and biocompatibility of these scaffolds and the safety and cost of their growth factors limit their clinical application. Therefore, it is critical to develop a novel scaffold modified with efficient growth factors that meets the requirements of BTE. Herein, 3D-printed poly (lactic-co-glycolic acid)/ hydroxyapatite (PLGA/HA) composite scaffolds modified with new fusion peptides, which can effectively promote the regeneration and repair of bone defects, were developed. 3D-printed PLGA/HA composite scaffolds with appropriate HA contents were prepared and had appropriate mechanical properties. In addition, the surface of the 3D-printed PLGA/HA composite scaffold was modified with new fusion peptides to provide osteogenic, antimicrobial, and angiogenesis-promoting effects. In vitro experiments showed that the fusion peptide-modified scaffolds had good biocompatibility and a certain degree of antibacterial activity. Moreover, the fusion peptidemodified scaffolds significantly improved the migration ability of BMSCs and Ea.hy926 cells, promoted the expression of osteogenesis-related factors (BMP2, RUNX2, ALP, OPN) in BMSCs, and promoted the expression of angiogenesis-related factors (VEGF and HIF-1 alpha) in Ea.hy926 cells. In vivo experiments showed that the fusion peptide-modified scaffolds had good osteogenic ability. This study reveals considerable application potential for bone defect repair and provides a new option of scaffold material for BTE.