Graphene Oxide Functionalized GelMA Platform Loaded With BFP-1 for Osteogenic Differentiation of BMSCs.

Spinal fusion is the ultimate choice for most patients with severe disc degeneration, and bone tissue engineering offers novel strategies to improve intervertebral bone growth and fusion. In this study, we utilized graphene oxide (GO) and methacrylated gelatin (GelMA) to prepare GelMA/GO composite hydrogel scaffolds with different GO concentrations. By characterizing the various properties of the scaffolds, it was learned that the composite scaffold containing 1.2 mg/mL GO possessed the best overall performance, and we used it for subsequent experiments. GelMA/GO composite scaffolds containing different bone-forming peptide-1 (BFP-1) concentrations were constructed and cocultured with bone marrow mesenchymal stem cells (BMSCs), and the results showed that GelMA/GO composite scaffolds containing 0.4 mg/mL BFP-1 induced the cells to produce more ALP and mineralized matrix. The above scaffold was further investigated as a GelMA/GO@BFP-1 composite, and the results showed that it promoted the production of ALP and mineralized matrix in BMSCs, and significantly enhanced the expression of osteogenesis-related genes (ALP, Runx-2, OCN, OPN) and proteins (Runx-2, OCN). It suggests that the GelMA/GO@BFP-1 complex promotes osteogenic differentiation of BMSCs and has the potential tobe used as a bone implant for improving intervertebral bone fusion.