Heterotopic Osteogenesis In Coaxial Bioelectrospun Tissue-Engineered Bone

This study is aimed to investigate the heterotopic osteogenesis potential of tissue-engineered bone fabricated using bioelectrospinning technology. A cell-scaffold composite was fabricated using coaxial bioelectrospinning, with 6% (w/v) Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) P34HB as the core and 8% (w/v) polyvinyl alcohol (PVA)/ gelatin (GEL) (volume ratio 1:3)/ human bone marrow mesenchymal stem cells (hBMSC) at a density of 1 × 10⁶ cells/mL as the shell. The composite was cultured with osteogenic media for 14 days as the experimental group, while the non-induced group served as the control. After 14 days of culture, the composites were implanted into the subcutaneous layer of nude mice for 8 or 16 weeks. Samples were collected for osteogenic histological staining and protein analysis. HE staining in the experimental group revealed more bone formation. Alizarin Red and Von Kossa staining observed increased mineral deposition, and type I collagen immunohistochemical staining showed stronger positive expression. Western-blot analysis further demonstrated enhanced expression of osteocalcin and type I collagen. No bone formation was observed in the control group. The P34HB-PVA/GEL/hBMSC composite fabricated by coaxial bioelectrospinning exhibited ectopic osteogenic potential. These findings suggest that coaxial bioelectrospinning has the potential to be a novel tissue engineering construction technique.