Tianjin Key Laboratory of Oral and Maxillofacial Function Reconstruction, Tianjin Stomatological Hospital, The Affiliated Stomatological Hospital of Nankai University, Tianjin 300041, China.
People's Hospital of Henan University of Traditional Chinese Medicine, Zhengzhou 450003, China.
ACS Biomater Sci Eng. 2023 Aug 14;9(8):4980-4993. doi: 10.1021/acsbiomaterials.3c00437. Epub 2023 Jul 10.
It has been well demonstrated that a dynamic culture environment improves tissue-engineered bone formation , but little is known about how cyclical mechanical loading induced bone formation in scaffolds . To mimic the organic and inorganic components and multilevel structure of a bony microenvironment, hydroxyapatite/β tricalcium phosphate/silk fibroin(HA/β-TCP/SF) composite scaffolds with macro- and micropores were fabricated in this study. The mechanical properties and structure of the scaffolds were adjusted based on the ratio of organic and inorganic components and three-dimensional (3D) printing parameters. Dynamic sinusoidal loading with different frequencies was applied to the composite scaffold. Mouse bone precursor cells MC3T3-E1 were seeded on the scaffolds, and the cell compatibility of the scaffolds was investigated by MTT, SEM, and HE. The effect of the loading on bone formation in the scaffold was investigated in a rabbit tibia defect model. The scaffold showed viscoelasticity and hysteresis under dynamic sinusoidal loading with different frequencies. With an increase in HA/β-TCP, the stress and modulus of the scaffolds increased. MTT, SEM, and HE results showed that MC3T3-E1 cells could adhere and proliferate on the composite scaffolds. After loading , the quantity of newly formed bone and the bone volume fraction increased. Micro-CT, undecalcified Van Gieson (VG) staining, and fluorescent double-labeling results suggested that appropriate cyclical mechanical loading at frequencies of 1 and 10 Hz had positive effects on bone formation in situ and it may play a role in clinical bone defect repair.
已有充分证据表明，动态培养环境可促进组织工程骨形成，但对于周期性机械加载如何诱导支架内骨形成知之甚少。为了模拟骨微环境的有机和无机成分以及多层次结构，本研究制备了具有大孔和微孔的羟基磷灰石/β-磷酸三钙/丝素蛋白（HA/β-TCP/SF）复合支架。根据有机和无机成分的比例以及三维（3D）打印参数调整了支架的机械性能和结构。对复合支架施加不同频率的动态正弦波加载。将小鼠成骨前体细胞 MC3T3-E1 接种到支架上，通过 MTT、SEM 和 HE 研究了支架的细胞相容性。在兔胫骨缺损模型中研究了加载对支架内骨形成的影响。支架在不同频率的动态正弦波加载下表现出粘弹性和滞后性。随着 HA/β-TCP 的增加，支架的应力和模量增加。MTT、SEM 和 HE 结果表明，MC3T3-E1 细胞可以在复合支架上黏附和增殖。加载后，新形成骨的数量和骨体积分数增加。微 CT、脱钙 Van Gieson（VG）染色和荧光双重标记结果表明，频率为 1 和 10 Hz 的适当周期性机械加载对原位骨形成有积极影响，可能在临床骨缺损修复中发挥作用。
