Department of Spine Surgery,Shenzhen Engineering Laboratory of Orthopaedic Regenerative Technologies, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong province, China.
School of Materials Science and Engineering, Peking University, Beijing, 100871, China.
Nat Commun. 2024 May 16;15(1):4160. doi: 10.1038/s41467-024-48417-8.
The regeneration of critical-size bone defects, especially those with irregular shapes, remains a clinical challenge. Various biomaterials have been developed to enhance bone regeneration, but the limitations on the shape-adaptive capacity, the complexity of clinical operation, and the unsatisfied osteogenic bioactivity have greatly restricted their clinical application. In this work, we construct a mechanically robust, tailorable and water-responsive shape-memory silk fibroin/magnesium (SF/MgO) composite scaffold, which is able to quickly match irregular defects by simple trimming, thus leading to good interface integration. We demonstrate that the SF/MgO scaffold exhibits excellent mechanical stability and structure retention during the degradative process with the potential for supporting ability in defective areas. This scaffold further promotes the proliferation, adhesion and migration of osteoblasts and the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. With suitable MgO content, the scaffold exhibits good histocompatibility, low foreign-body reactions (FBRs), significant ectopic mineralisation and angiogenesis. Skull defect experiments on male rats demonstrate that the cell-free SF/MgO scaffold markedly enhances bone regeneration of cranial defects. Taken together, the mechanically robust, personalised and bioactive scaffold with water-responsive shape-memory may be a promising biomaterial for clinical-size and irregular bone defect regeneration.
对于临界尺寸骨缺损，特别是形状不规则的骨缺损的再生，仍然是一个临床挑战。已经开发出各种生物材料来增强骨再生，但在形状适应性、临床操作复杂性和不令人满意的成骨生物活性方面的限制，极大地限制了它们的临床应用。在这项工作中，我们构建了一种机械强度高、可定制和对水响应的形状记忆丝素/氧化镁（SF/MgO）复合材料支架，它能够通过简单的修剪快速匹配不规则的缺损，从而实现良好的界面整合。我们证明 SF/MgO 支架在具有潜在支撑能力的缺损区域的降解过程中表现出优异的机械稳定性和结构保持能力。该支架进一步促进了成骨细胞的增殖、黏附和迁移，以及骨髓间充质干细胞（BMSCs）的成骨分化。在合适的氧化镁含量下，支架具有良好的组织相容性、低异物反应（FBRs）、显著的异位矿化和血管生成。雄性大鼠颅骨缺损实验表明，无细胞 SF/MgO 支架显著增强了颅骨缺损的骨再生。总之，这种具有机械强度、个性化和水响应形状记忆功能的生物活性支架可能是一种很有前途的临床尺寸和不规则骨缺损再生的生物材料。
