Recently, extracellular matrix-based tissue-engineered bone is a promising approach to repairing bone defects, and the seed cells are mostly mesenchymal stem cells. However, bone remodelling is a complex biological process, in which osteoclasts perform bone resorption and osteoblasts dominate bone formation. The interaction and coupling of these two kinds of cells is the key to bone repair. Therefore, the extracellular matrix secreted by the mesenchymal stem cells alone cannot mimic a complex bone regeneration microenvironment, and the addition of extracellular matrix by preosteoclasts may contribute as an effective strategy for bone regeneration. Here, we established the mesenchymal stem cell/preosteoclast extracellular matrix -based tissue-engineered bones and demonstrated that engineered-scaffolds based on mesenchymal stem cell/ preosteoclast extracellular matrix significantly enhanced osteogenesis in a 3 mm rat femur defect model compared with mesenchymal stem cell alone. The bioactive proteins released from the mesenchymal stem cell/ preosteoclast extracellular matrix based tissue-engineered bones also promoted the migration, adhesion, and osteogenic differentiation of mesenchymal stem cells in vitro. As for the mechanisms, the iTRAQ-labeled mass spectrometry was performed, and 608 differentially expressed proteins were found, including the IGFBP5 and CXCL12. Through in vitro studies, we proved that CXCL12 and IGFBP5 proteins, mainly released from the preosteoclasts, contributed to mesenchymal stem cells migration and osteogenic differentiation, respectively. Overall, our research, for the first time, introduce pre-osteoclast into the tissue engineering of bone and optimize the strategy of constructing extracellular matrix–based tissue-engineered bone using different cells to simulate the natural bone regeneration environment, which provides new sight for bone tissue engineering.

最近，基于细胞外基质的组织工程骨是修复骨缺损的一种有前途的方法，种子细胞主要是间充质干细胞。但是，骨重塑是一个复杂的生物学过程，破骨细胞在其中进行骨吸收，而成骨细胞在骨形成中起主导作用。这两种细胞的相互作用和偶联是骨修复的关键。因此，仅由间充质干细胞分泌的细胞外基质不能模拟复杂的骨再生微环境，破骨细胞添加细胞外基质可能有助于骨再生的有效策略。这里，我们建立了基于间充质干细胞/破骨细胞破细胞外基质的组织工程骨骼，并证明了基于间充质干细胞/破骨细胞破细胞外基质的工程支架与单独的间充质干细胞相比，在3mm大鼠股骨缺损模型中显着增强了成骨作用。从间充质干细胞/破骨细胞破细胞外基质为基础的组织工程化骨骼中释放的生物活性蛋白还促进了间充质干细胞的体外迁移，粘附和成骨分化。至于机制，进行了iTRAQ标记的质谱分析，发现了608个差异表达的蛋白质，包括IGFBP5和CXCL12。通过体外研究，我们证明了CXCL12和IGFBP5蛋白（主要从破骨细胞释放），分别促成间充质干细胞迁移和成骨分化。总体而言，我们的研究首次将破骨细胞引入骨的组织工程中，并优化了使用不同细胞模拟天然骨再生环境构建基于细胞外基质的组织工程化骨的策略，这为骨组织工程。