Bioactive gelatin cryogels with BMP-2 biomimetic peptide and VEGF: A potential scaffold for synergistically induced osteogenesis

ABSTRACT A poor biocompatibility and bioactivity of invasive materials remains major problems for biomaterial-based therapy. In this study, we introduced gelatin scaffolds carrying both bone morphogenetic protein-2 (BMP-2) biomimetic peptide and vascular endothelial growth factor-165 (VEGF) that achieved controlled release, cell attachment, proliferation and differentiation. To promote osteogenesis with VEGF, we designed the BMP-2 biomimetic peptide that comprised BMP-2 core sequence oligopeptide (SSVPT), phosphoserine, and synthetic cell adhesion factor (RGDS). In vitro cell experiments, the scaffold was conducive to the adhesion and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs). The micro-CT 3D reconstruction of the rat cranial bone defect model showed that bone regeneration patterns occurred from one side edge towards the center area implanted with the prepared cryogel, and tissue section staining analysis demonstrated that the scaffold with double-growth factor can synergistically accelerate bone regeneration. These findings suggested that the obtained gelatin cryogel could serve as a cell-responsive platform for biomaterial-based nonbearing bone repair.