应力作用下Gli1介导YAP调控间充质干细胞聚合体分化促进牙周再生的机制研究

本课题组模拟发育早期的细胞凝聚机制，原创建立了间充质干细胞聚合体（MSCA）技术，国际首次实现全牙髓再生的转化应用治疗，但口腔力学环境下牙周再生效果不甚满意。课题组前期研究发现应力能影响MSCA在牙周微环境中的分化再生潜能；并证实Gli1+MSC是MSCA形成中一类特异性细胞亚群， Gli1可以响应生物力学刺激介导转录因子YAP进而调控MSC分化，但其具体作用机制尚不清楚。故本项目拟利用Gli1+MSC剔除、YAP条件性敲除等模式小鼠，三维动态培养制备MSCA，观察生物力学信号对Gli1+MSC生物学性能的影响，检测Gli1和YAP响应力学信号调控MSCA的作用模式，分析Gli1调控YAP诱导MSCA牙周分化的机制，改进制备MSCA并评估其用于牙周再生的功效，以期阐明应力作用下Gli1介导YAP通路调节MSCA特异性分化实现牙周再生的机制，为牙周再生临床转化应用提供实验依据。

Our previous studies have originally established the mesenchymal stem cells aggregate (MSCA) via mimicing the mechanism of cell condensation in the early stage of development. And total length pulp regeneration has been achieved after clinical transformation and application with MSCA for the first time. However, the regeneration of periodontium remains unsatisfactory. Our preliminary study have found that stress can affect the differentiation and regeneration potential of MSCA in periodontal microenvironment. Moreover, Gli1+ cell are a specific MSC subpopulation in MSCA formation, which can mediate classical mechanotransduction factor Yes-associated protein (YAP) in response to biomechanical stimuli to regulate MSCs differentiation. However, the specific mechanism remains elusive. This project intends to utilize Gli1+MSC elimination and YAP conditional knockout model mice to establish a dynamic culture strategy for MSCA preparation and to observe the influence of biomechanical signals on MSCA biological propertie. In addition, the model of Gli1 and YAP regulating MSCA in response to mechanical signals will be detected, the mechanism of Gli1 regulating the differentiation of MSCA induced by YAP will be analyzed and the efficacy of its application in periodontal regeneration will be evaluated. The aim of the project is to elucidate the mechanism of Gli1 regulating YAP under stress to induce the specific differentiation of MSCA to achieve periodontal regeneration, which provide experimental basis for clinical trasformation and application in periodontal regeneration.