肌源干细胞（MDSCs）在开放性骨折的骨愈合过程中起关键作用，但负压状态能否促进MDSCs的增殖及成骨分化尚不清楚。我们前期研究发现，负压状态可促进骨膜间充质干细胞的增殖及成骨分化；同时，实验发现负压联合植骨可促进骨缺损的愈合。因此提出负压状态可促进MDSCs成骨分化的假设。本项目组拟系统地研究负压促进MDSCs成骨分化的作用及可能的分子机制。拟在负压状态下的生物反应器内培养MDSCs，研究负压作用对MDSCs增殖及成骨分化的影响；构建HIF-1α过表达的MDSCs，并研究在负压状态下HIF-1α对MDSCs增殖及成骨分化的影响；并建立开放性骨折动物模型，研究在负压状态下MDSCs在骨愈合过程中的作用，研究可能的分子机制，为临床应用提供理论依据。

Muscle-derived stem cells (MDSCs) plays a central role during the process of bone healing in open fracture. However, whether negative pressure wound therapy (NPWT) can promote MDSCs proliferation and osteogenic differentiation is unclear. Our precious work showed NPWT could promote proliferation and osteogenic differentiation in periosteal mesenchymal stem cell. Moreover, our previous experiments found that NPWT combined with bone graft may promote bone healing of bone defects. Therefore, we assume that the NPWT may promote osteogenic differentiation of MDSCs. The aim of the present project is to investigate the effect and mechanism of negative pressure on osteogenic differentiation in MDSCs. MDSCs are cultured under negative pressure, the proliferation and osteogenic differentiation are determined. Cell lines with HIF-1α overexpression are established to investigate the role of HIF-1α in the proliferation and osteogenic differentiation under negative pressure. Open fractures animal model is established to study the role of MDSCs under negative pressure in the formation of new bone.