Osteoprogenitor mobilization for bone development and repair

摘要 由创伤性损伤或肿瘤切除引起的大骨缺损构成了重大的临床挑战，因为它们 如果不进行干预就不能愈合，并且目前的骨移植疗法是有限的。组织工程是一种 这是一种有前景的替代方案，但通常受到内源性祖细胞的不良募集或供应的限制。不像 大的缺损，骨折愈合容易重演骨发育的步骤。在骨折修复中， 机械线索，以片段间应变的形式，对于确定骨 形成，即通过膜内骨化或间接骨形成 通过软骨内骨化形成，其中软骨模板首先形成，随后被替换为 骨头骨发育过程中骨祖细胞动员的机制以及如何动员 对直接骨折修复的机械线索知之甚少。我们观察到的组合作用， 机械敏感性转录辅激活因子，Yes相关蛋白（雅普）和转录辅激活因子 PDZ基序（TAZ）在促进骨发育和修复中的作用。此应用程序的目标是定义 雅普/TAZ在骨发育过程中骨祖细胞动员中的机制作用， 机械载荷介导的骨折修复。实现这一目标将为发展提供新的见解。 骨骼疾病，确定可以利用的途径，以加强愈合，并定位我们设计新的 组织工程策略，概括骨发育和自然修复的过程， 大骨缺损的再生。

Abstract Large bone defects caused by traumatic injury or tumor resection pose a significant clinical challenge as they cannot not heal without intervention, and current bone grafting therapies are limited. Tissue engineering is a promising alternative, but is often limited by poor recruitment or supply of endogenous progenitor cells. Unlike large defects, bone fractures heal readily by recapitulating the steps of bone development. In fracture repair, mechanical cues, in the form of interfragmentary strains, are essential to determine the pathway by which bone formation occurs, namely direct bone formation through intramembranous ossification or indirect bone formation through endochondral ossification, in which a cartilage template forms first and is later replaced by bone. The mechanisms by which osteoprogenitor cells are mobilized during bone development and how mechanical cues direct fracture repair are poorly understood. We observed combinatorial roles of the mechanosensitive transcriptional co-activators, Yes-associated protein (YAP) and Transcriptional co-activator with PDZ-motif (TAZ) in promoting both bone development and repair. The goal of this application is to define the mechanistic roles of YAP/TAZ in osteoprogenitor cell mobilization during bone development and mechanical load-mediated fracture repair. Accomplishing this goal will provide new insights into developmental bone diseases, identify pathways that could be exploited to enhance healing, and position us to design new tissue engineering strategies that recapitulate the processes of bone development and natural repair for regeneration of large bone defects.