Engineering 3D biomimetic osteogenesis imperfecta models to dissect mechanisms of N-cadherin mediated osteoblast-endothelial function

项目摘要/摘要 成骨不全(OI)是一种罕见的疾病，其特征是骨形成不足和不适当 导致骨骼脆弱。OI是由主要ECM的功能丧失或显性-负突变引起的 组分，命名为1型胶原(由COL1A1/COL1A2基因组成)。目前还没有治愈OI的方法， 就骨折复位和骨骼功能而言，目前治疗方法的长期益处仍不清楚。 氧合作用影响骨稳态，这是由不同类型细胞的功能和它们的空间排列决定的 在三维(3D)中通过与胶原支架结合。具体来说，信号之间的相互作用 内皮细胞、神经细胞、成骨细胞、破骨细胞、骨细胞及其共享的胶原基质可能控制 它们的功能和显著影响骨骼的动态平衡。(目标1)为了使每个小区对OI的贡献脱钩，我们 将开发一个强大的临床前筛查模型，基于芯片上的器官技术，概括地说 骨微血管与周围细胞形成的微血管，如成骨细胞。这个平台将用于药物 筛选和鉴定新的OI治疗药物，避免体内费力和昂贵的限制 以及体外研究。(目标2)为了进一步扩大我们的研究，我们将使用这些类似3D疾病的芯片上的器官 旨在识别OI和OI的新基因靶点的COL1A1异源细胞机制研究系统 最终，制定新的预防战略。具体地说，我们的目标是了解坚持者的角色 骨微血管中连接蛋白分子N-钙粘附素的研究 成骨细胞-内皮细胞偶联。鉴于公认的多细胞复杂性的基本重要性 众多的骨骼疾病，这些体外模型将解偶联参与的重要机制 多参数骨相关疾病，如骨质疏松症或骨癌。总体而言，这些新的体外培养 微生理系统可以被认为是特定患者的受控的物理表现，因此 可直接应用于临床，为疾病的治疗或预防策略提供信息。

Project Summary/Abstract Osteogenesis Imperfecta (OI) is a rare disease characterized by low and inappropriate bone formation resulting in bone fragility. OI is caused by loss-of-function or dominant-negative mutations in a major ECM component, named type 1 collagen (composed of COL1A1/COL1A2 genes). There is currently no cure for OI, and long-term benefits of current treatments remain unclear in terms of fracture reduction and bone functionality. OI affects bone homeostasis which is governed by the function of various cell types and their spatial arrangement in three-dimensions (3D) through association with collagen scaffolds. Specifically, signaling interactions among endothelial cells, nerve cells, osteoblasts, osteoclasts, osteocytes and their shared collagen matrix may control their function and dramatically impact bone homeostasis. (Aim 1) To decouple each cell contribution to OI, we will develop a robust preclinical screening model, based on the organ-on-a-chip technology, that recapitulates the bone microvasculature with the surrounding cells, such as osteoblasts. This platform will be used for drug screening and identification of new OI therapeutics, avoiding the limitations of laborious and expensive in vivo and in vitro studies. (Aim 2) To further expand our studies, we will use these 3D disease-like organ-on-a-chip systems to dissect the heterocellular mechanisms of COL1A1 aiming at identifying new gene targets for OI and ultimately, developing new strategies for prevention. Specifically, we aim to understand the role of an adheren junctions (AJs) molecule, named N-cadherin in bone microvasculature by dissecting the mechanisms mediating osteoblast-endothelial coupling. Given the recognized fundamental importance of multicellular complexity in numerous bone diseases, these in vitro models would decouple important mechanisms involved in multiparametric bone-related diseases such as osteoporosis or bone cancer. Overall, these new in vitro microphysiological systems can be regarded as controlled, physical representations of specific patients and therefore be applied directly in the clinic to inform strategies for treatment or prevention of disease.