脂肪干细胞微泡携带let-7促进游离脂肪移植后血管新生作用与机制研究

自体脂肪移植是目前软组织填充的首选方案，但由于移植早期的缺血缺氧环境导致移植物中大量脂肪细胞坏死吸收，从而限制了其临床推广。如何促进移植物快速建立充分的血供是保障其存活的关键。我们前期研究发现，由脂肪干细胞旁分泌的微泡（ASC-MVs）可携带具有促血管化作用的miRNA let-7进入血管内皮细胞并促进其迁移和管样分化。进一步研究发现ASC-MVs还能促进游离脂肪移植后血管新生，据此我们推测ASC-MVs可向移植区的血管内皮细胞传递let-7从而加速血管新生。本研究拟围绕这个重要的科学问题展开，采用组织移植、蛋白生化、基因沉默、体外三维血管构建等技术,重点研究在缺血缺氧环境下ASC-MVs调控血管内皮细胞管样分化作用，ASC-MVs传递let-7的机制，let-7促进血管新生的关键信号通路，以揭示ASC-MV促进游离脂肪移植后血管新生的主要途径，为其在游离脂肪移植领域的运用提供实验依据。

Autologous fat transplantation is an ideal choice to repair tissue defects.But it has hit a bottleneck on its therapeutic effect due to the ischemia and hypoxia which lead to the death of many adipose cells.How to trigger angiogenesis as soon as possible becomes a vital issue.Base on our previous study,it has been proved that the microvesicles secreted by adipose-derived stem cells(ASC-MVs) carring angiogenesis miRNA let-7 can improve the migration and angiogenesis of human vascular endothelial cells,and its mechanism may land on that ASC-MVs can transfer angiogenesis microRNA to vasular endothelial cells.Base on our preliminary experiment,ASC-MVs can accelerate angiogenesis after free fat graft.But its mechanism is not clear.Thus,the following research will focus on the mechanism of angiogenesis leaded by ASC-MVs in ischemia and hypoxia,the mechanism of ASC-MVs transfering angiogenesis microRNA and accelerating angiogenesis after free fat graft via by techniques concerning tissue transplation, protein biochemistry,genetic testing and three-dimensional vessel building.The fruit of these research will offer reliable theorethical basis and experimental evidence to the application of ASC-MVs in free fat graft.