Department of Orthopedic Surgery, 909th Hospital of People's Liberation Army, Affiliated Southeast Hospital of Xiamen University, 269 Zhanghua Middle Road, Fujian Province, 363000, Zhangzhou, People's Republic of China.
Cell Tissue Res. 2021 Sep;385(3):639-658. doi: 10.1007/s00441-021-03458-z. Epub 2021 May 8.
In this study, effects of combining optimized tissue engineering bone (TEB) implantation with heel-strike like mechanical loading to repair segmental bone defect in New Zealand rabbits were investigated. Physiological characteristics of bone marrow mesenchymal stem cells (BMMSCs), compact bone cells (CBCs), and bone marrow and compact bone coculture cells (BMMSC-CBCs) were compared to select the optimal seed cells for optimized TEB construction. Rabbits with segmental bone defects were treated in different ways (cancellous bone scaffold for group A, cancellous bone scaffold and mechanical loading for group B, optimized TEB for group C, optimized TEB and mechanical loading for group D, n = 4), and the bone repair were compared. BMMSC-CBCs showed better proliferation capacity than CBCs (p < 0.01) and stronger osteogenic differentiation ability than BMMSCs (p < 0.05). Heel-strike like mechanical loading improved proliferation and osteogenic differentiation ability and expression levels of TGFβ1 as well as BMP2 of seed cells in vitro (p < 0.05). At week 12 post-operation, group D showed the best bone repair, followed by groups B and C, while group A finished last (p < 0.05). During week 4 to 12 post-operation, group D peaked in terms of expression levels of TGFβ1, BMP2, and OCN, followed by groups B and C, while group A finished last (p < 0.05). Thus, BMMSC-CBCs showed good proliferation and osteogenic differentiation ability, and they were thought to be better as seed cells than BMMSCs and CBCs. The optimized TEB implantation combined with heel-strike like mechanical loading had a synergistic effect on bone defect healing, and enhanced expression of TGFβ1 and BMP2 played an important role in this process.
本研究旨在探讨优化组织工程骨（TEB）植入联合足跟冲击样机械加载对新西兰兔节段性骨缺损修复的影响。比较骨髓间充质干细胞（BMMSCs）、皮质骨细胞（CBCs）和骨髓与皮质骨共培养细胞（BMMSC-CBCs）的生理特性，以选择优化 TEB 构建的最佳种子细胞。将节段性骨缺损兔分为不同处理组（A 组松质骨支架，B 组松质骨支架和机械加载，C 组优化 TEB，D 组优化 TEB 和机械加载，n=4），比较骨修复情况。BMMSC-CBCs 的增殖能力优于 CBCs（p<0.01），成骨分化能力优于 BMMSCs（p<0.05）。足跟冲击样机械加载可提高种子细胞的增殖和成骨分化能力以及 TGFβ1 和 BMP2 的表达水平（p<0.05）。术后 12 周，D 组骨修复效果最佳，其次是 B 组和 C 组，A 组最差（p<0.05）。术后 4~12 周，D 组 TGFβ1、BMP2 和 OCN 的表达水平最高，其次是 B 组和 C 组，A 组最低（p<0.05）。因此，BMMSC-CBCs 具有良好的增殖和成骨分化能力，作为种子细胞优于 BMMSCs 和 CBCs。优化 TEB 植入联合足跟冲击样机械加载对骨缺损愈合具有协同作用，增强 TGFβ1 和 BMP2 的表达在这一过程中发挥重要作用。
