Eichholz Kian F, Von Euw Stanislas, Burdis Ross, Kelly Daniel J, Hoey David A
Department of Mechanical, Aeronautical and Biomedical Engineering, Materials and Surface Science Institute, University of Limerick, Limerick, V94 T9PX, Ireland.
Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Pearse Street, Dublin 2, D02 R590, Ireland.
Adv Healthc Mater. 2020 Dec;9(24):e2001102. doi: 10.1002/adhm.202001102. Epub 2020 Oct 27.
The hierarchical structure of bone plays pivotal roles in driving cell behavior and tissue regeneration and must be considered when designing materials for orthopedic applications. Herein, it is aimed to recapitulate the native bone environment by using melt electrowriting to fabricate fibrous microarchitectures which are modified with plate-shaped (pHA) or novel nanoneedle-shaped (nnHA) crystals. Nuclear magnetic resonance spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction demonstrate that these coatings replicate the nanostructure and composition of native bone. Human mesenchymal stem/stromal cell (MSC) mineralization is significantly increased fivefold with pHA scaffolds and 14-fold with nnHA scaffolds. Given the protein stabilizing properties of mineral, these materials are further functionalized with bone morphogenetic protein 2 (BMP2). nnHA treatment facilitates controlled release of BMP2 which further enhance MSC mineral deposition. Finally, the versatility of this nnHA treatment method, which may be used to coat different architectures/materials including fused deposition modeling (FDM) scaffolds and Ti6Al4V titanium, is demonstrated. This study thus outlines a method for fabricating scaffolds with precise fibrous microarchitectures and bone-mimetic nnHA extrafibrillar coatings which significantly enhance MSC osteogenesis and therapeutic protein delivery, and leverages these results to show how this surface treatment method may be applied to a wider field for multiple orthopedic applications.
骨骼的分层结构在驱动细胞行为和组织再生中起着关键作用，在设计骨科应用材料时必须予以考虑。在此，旨在通过熔体静电纺丝制造纤维微结构来重现天然骨环境，这些微结构用板状（pHA）或新型纳米针状（nnHA）晶体进行了修饰。核磁共振光谱、扫描电子显微镜、透射电子显微镜和X射线衍射表明，这些涂层复制了天然骨的纳米结构和组成。使用pHA支架时人间充质干/基质细胞（MSC）矿化显著增加了五倍，使用nnHA支架时增加了14倍。鉴于矿物质的蛋白质稳定特性，这些材料进一步用骨形态发生蛋白2（BMP2）进行功能化。nnHA处理促进了BMP2的控释，这进一步增强了MSC矿物质沉积。最后，展示了这种nnHA处理方法的通用性，它可用于涂覆不同的结构/材料，包括熔融沉积建模（FDM）支架和Ti6Al4V钛。因此，本研究概述了一种制造具有精确纤维微结构和仿生nnHA纤维外涂层支架的方法，该方法显著增强了MSC成骨作用和治疗性蛋白质递送，并利用这些结果展示了这种表面处理方法如何应用于更广泛的领域以用于多种骨科应用。
