Trop2对CBSCs移植修复梗死心肌的影响及机制研究

A recent study demonstrated that cortical bone derived stem cells (CBSCs) have been shown to enhance more effective cell therapies than cardiac stem cells post myocardial infarction, while the mechanisms involved remain unknown. Our previous studies indicated that Trop2, involved in regulating the self-renewal of stem-like cells, is more highly expressed in CBSCs than in cardiac stem cells, and demonstrated that Trop2 is linked to maintain the abilities of proliferation or differentiation for CBSCs by studying the trop2 knockout mouse model. Our pre-experiments found that Trop2 can help improve the murine cardiac function after transendocardial CBSCs injection post MI. Thus, Trop2 may be associated with the better effects of CBSC-mediated cardiac regeneration. ..To investigate the potential mechanisms between Trop2 and CBSC-mediated cardiac regeneration post MI, the project intends to track the fate or destination of CBSCs in vivo with fluorescence-activated cellsorter (FACS) and confocal scanning laser microscopy (CSLM) by studying a double transgenic mouse model (trop2 KO/EGFP+ mouse); to demonstrate the differences in survival, proliferation, differentiation, and paracrine effects between the CBSCs derived from WT and trop2 KO mice under hypoxic microenvironment in vitro with FACS, CSLM and ELISA; to verify the regulation of AKT/β-Catenin signaling pathway by Trop2 through WB, IP and Liquid Chromatography-Mass Spectrometry(LC-MS). Our project may help to further clarify the molecular mechanisms of CBSC-mediated cardiac repair and may be crucial for the development of targeted preconditioning and genetic manipulation approaches by which will likely be useful to enhance the therapeutic benefit...

最新研究发现骨密质来源干细胞（CBSCs）移植修复梗死心肌的能力优于心脏干细胞，但分子机制不明。项目申请人前期研究发现①Trop2在CBSCs的表达高于心脏干细胞；②Trop2的表达比Trop2的缺失更有助于CBSCs移植对心梗小鼠心功能的改善。据此推测Trop2可能与CBSCs优越的修复性能相关。为了深入研究Trop2促进CBSCs移植修复梗死心肌的作用机制，本项目拟采用携带绿色荧光的trop2 基因敲除小鼠，分离出荧光标记的CBSCs，通过FACS、ELISA以及激光共聚焦技术等对比研究Trop2(＋)与Trop2(－)CBSCs在体内心梗局部以及体外缺氧微环境的存活、分化及旁分泌等的差异；运用WB、IP及LC-MS等方法确证Trop2通过AKT/β-Catenin信号途径对上述作用进行调控，揭示其再生修复的分子机制，为干细胞的靶向预处理和合理基因修饰奠定实验基础。