Zhang Yali, Xia Lunguo, Zhai Dong, Shi Mengchao, Luo Yongxiang, Feng Chun, Fang Bing, Yin Jingbo, Chang Jiang, Wu Chengtie
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, People's Republic of China.
Nanoscale. 2015 Dec 7;7(45):19207-21. doi: 10.1039/c5nr05421d. Epub 2015 Nov 3.
The hierarchical microstructure, surface and interface of biomaterials are important factors influencing their bioactivity. Porous bioceramic scaffolds have been widely used for bone tissue engineering by optimizing their chemical composition and large-pore structure. However, the surface and interface of struts in bioceramic scaffolds are often ignored. The aim of this study is to incorporate hierarchical pores and bioactive components into the bioceramic scaffolds by constructing nanopores and bioactive elements on the struts of scaffolds and further improve their bone-forming activity. Mesoporous bioactive glass (MBG) modified β-tricalcium phosphate (MBG-β-TCP) scaffolds with a hierarchical pore structure and a functional strut surface (∼100 nm of MBG nanolayer) were successfully prepared via 3D printing and spin coating. The compressive strength and apatite-mineralization ability of MBG-β-TCP scaffolds were significantly enhanced as compared to β-TCP scaffolds without the MBG nanolayer. The attachment, viability, alkaline phosphatase (ALP) activity, osteogenic gene expression (Runx2, BMP2, OPN and Col I) and protein expression (OPN, Col I, VEGF, HIF-1α) of rabbit bone marrow stromal cells (rBMSCs) as well as the attachment, viability and angiogenic gene expression (VEGF and HIF-1α) of human umbilical vein endothelial cells (HUVECs) in MBG-β-TCP scaffolds were significantly upregulated compared with conventional bioactive glass (BG)-modified β-TCP (BG-β-TCP) and pure β-TCP scaffolds. Furthermore, MBG-β-TCP scaffolds significantly enhanced the formation of new bone in vivo as compared to BG-β-TCP and β-TCP scaffolds. The results suggest that application of the MBG nanolayer to modify 3D-printed bioceramic scaffolds offers a new strategy to construct hierarchically porous scaffolds with significantly improved physicochemical and biological properties, such as mechanical properties, osteogenesis, angiogenesis and protein expression for bone tissue engineering applications, in which the incorporation of nanostructures and bioactive components into the scaffold struts synergistically play a key role in the improved bone formation.
生物材料的分级微观结构、表面和界面是影响其生物活性的重要因素。通过优化其化学成分和大孔结构，多孔生物陶瓷支架已被广泛应用于骨组织工程。然而，生物陶瓷支架中支柱的表面和界面常常被忽视。本研究的目的是通过在支架支柱上构建纳米孔和生物活性元素，将分级孔隙和生物活性成分纳入生物陶瓷支架，并进一步提高其骨形成活性。通过3D打印和旋涂成功制备了具有分级孔隙结构和功能性支柱表面（约100nm的MBG纳米层）的介孔生物活性玻璃（MBG）改性β-磷酸三钙（MBG-β-TCP）支架。与没有MBG纳米层的β-TCP支架相比，MBG-β-TCP支架的抗压强度和磷灰石矿化能力显著提高。与传统生物活性玻璃（BG）改性β-磷酸三钙（BG-β-TCP）和纯β-TCP支架相比，MBG-β-TCP支架中兔骨髓基质细胞（rBMSCs）的附着、活力、碱性磷酸酶（ALP）活性、成骨基因表达（Runx2、BMP2、OPN和Col I）和蛋白质表达（OPN、Col I、VEGF、HIF-1α）以及人脐静脉内皮细胞（HUVECs）的附着、活力和血管生成基因表达（VEGF和HIF-1α）均显著上调。此外，与BG-β-TCP和β-TCP支架相比，MBG-β-TCP支架在体内显著增强了新骨的形成。结果表明，应用MBG纳米层修饰3D打印生物陶瓷支架为构建具有显著改善的物理化学和生物学性能（如机械性能、成骨、血管生成和蛋白质表达）的分级多孔支架提供了一种新策略，用于骨组织工程应用，其中将纳米结构和生物活性成分纳入支架支柱在改善骨形成中协同发挥关键作用。
