microRNA诱导血管平滑肌细胞转分化成内皮细胞的作用和机制研究

转分化是指终分化的细胞在转录因子诱导下发生重编码，分化为另外一种细胞类型。转分化大多采用成纤维细胞分化成其它终分化细胞，分化后的细胞一般都具有相应的功能并避免了肿瘤的副作用而日益受到关注。我们前期采用microRNA芯片数据辅以FACS技术，首次利用microRNA将血管平滑肌细胞转分化成内皮细胞（iEC），初步的研究显示该细胞具有血管内皮细胞部分功能。申请者拟在后续工作中，从免疫组化、流式分选、Matrigel、缺血动物模型等鉴定该iEC是否具有完善的正常血管内皮细胞功能，并采用遗传谱系追踪进一步明确血管平滑肌细胞可直接分化成血管内皮细胞。此外，我们还将采用Western blot、流式等方法进一步探讨转分化中重编码基因的表达和具体的信号通路，以阐明该microRNA鸡尾酒转分化的机制，并进一步提高转分化效率。此项研究不仅对血管发育具有重要理论价值，而且为血管疾病的治疗提供新的思路。

Transdifferentiation is refers to the reprogramming and differentiation of the terminal differentiated cells into another type of cells by transcription factor. Transdifferentiation research mostly use fibroblasts for target cells and this techniques are generally gotten increasingly attention due to the effect. In our early research, we differentiate vascular smooth muscle cells into endothelial cells (iEC) for the first time by transfected with microRNA, basing on the information from microRNA chip and FACS technology. The preliminary research shows the iECs have functions of vascular endothelial cells. Next, we are planning to identify whether the iEC has perfect normal vascular endothelial cell function through the immunohistochemical, FACS, Matrigel, and ischemic animal model, and use the genetic lineage tracing to identify whether vascular smooth muscle cells can differentiate into endothelial cells directly. In addition, we will also adopt Western blot and flow methods to further explore the gene expression of reprogramming in transdifferentiation and the specific signaling pathways, to clarify the mechanism of microRNA cocktails, and further improve the efficiency of transdifferentiation. The study has important theoretical value, not only to the blood vessel development and will provide a new method for the treatment of vascular diseases.