Endothelial cell specification at the osteogenic and angiogenic interface in cranial bone tissue engineering

颅骨组织工程中成骨和血管生成界面的内皮细胞规范

基本信息

批准号：
10252906
负责人：
XINPING ZHANG
金额：
$ 53.64万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-03 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10252906
关键词：
APLN gene Address Affect Aging Allografting Arteries Autologous Transplantation BMX gene Biological Markers Blood Vessels Blood capillaries Bone Regeneration Bone Tissue Cardiovascular system Cells Cephalic Clinical Coupling Defect Development Embryonic Development Endothelial Cells Endothelium Engineering Excision Genetic Engineering Goals Hypoxia Hypoxia Pathway Image Imaging technology Implant Infection Knowledge Label Laser Scanning Microscopy Lead Mediating Metabolic Metaphysis Modeling Molecular Profiling Morphology NADH Natural regeneration Nature Nicotinamide adenine dinucleotide Orthopedic Procedures Osteoblasts Osteogenesis Oxidation-Reduction Oxygen PECAM1 gene Pathway interactions Perfusion Play Population Regulation Resolution Role Series Site Tamoxifen Time Tissue Engineering Tissues Trauma Vascularization Veins Venous angiogenesis base blood vessel development bone bone loss craniomaxillofacial fluorescence lifetime imaging gain of function genetic approach genetic manipulation hypoxia inducible factor 1 imaging approach imaging genetics improved insight intravital imaging long bone loss of function migration mouse model nanofiber novel osteogenic overexpression postnatal reconstruction regenerative repair model repaired response scaffold success tissue oxygenation tissue repair transcriptome sequencing tumor two-photon vascular bed

项目摘要

Abstract Repair and reconstruction of bone loss due to tumor resection, trauma and infection remains a significant clinical challenge. Worldwide, autografts or allografts are used in approximately 3 million orthopaedic procedures annually, of which 6% are craniomaxillofacial in nature. Bone tissue engineering has been hailed as the ultimate solution for replacing bone autograft in repair of bone defects. However, the long-term success of bone tissue engineering is impeded by inadequate vascularization of the engineered construct. The current lack of progress in vascularization of tissue engineered scaffold is attributed to our incomplete understanding of angiogenesis and vascular beds in bone repair and regeneration. A functional blood vessel network consists of arteries, veins and a capillary interface that connects arterial and venous microvessels for proper vascular perfusion. While the specification of arterial and venous endothelium has been well studied during early embryonic development, the postnatal regulation of arterial and venous expansion and specification at capillary level during repair and regeneration is poorly understood. A series of recent studies have suggested that hypoxia affects the endothelial cell (EC) specification at the osteogenic and angiogenic interface in development and aging. Genetic manipulation of the hypoxia inducible factor 1 (HIF-1) pathway markedly affects the formation of specific subsets of capillary vessels, termed Type H (CD31highEmcnhigh) vessels that couple to OSX+ osteoblasts at the long bone metaphysis. To gain a better understanding of the critical role of hypoxia at the osteogenic and angiogenic interface in repair and regeneration, we established a series of novel imaging approaches that permit high resolution, quantitative, and functional analyses of capillary vessels that couple to Col (I) 2.3 GFP+ osteoblasts at a cranial bone defect site. Utilizing these novel imaging approaches in a layer-by-layer enabled, nanofiber-mediated cranial defect repair model, we demonstrate that osteogenesis- dependent angiogenesis consists of morphologically and functionally distinct CD31+Emcn+ and CD31+Emcn- vessels. Examination of blood vessel type distribution and bone regeneration demonstrates differential angiogenic responses and contrasting distributions of CD31+Emcn+ and CD31+Emcn- vessels associated with Col I (2.3) GFP+ osteoblasts, new bone and non-bone forming tissue, suggesting that EC specification at the capillary level is a key component of osteogenesis-dependent angiogenesis in bone repair and regeneration. Based on these findings, we propose to examine the effects of hypoxia on EC specification and the impact of dysregulation of EC specification on bone formation during cranial defect repair and regeneration. Three complementary Aims will combine imaging, genetic and engineering approaches to defining the osteogenesis- dependent EC specification and the role of hypoxia in repair and regeneration. The success of our study will provide novel insights into mechanisms of osteogenesis and angiogenesis in repair, potentially offering novel translational targets for bone regeneration.

抽象的由于肿瘤切除、创伤和感染导致的骨丢失的修复和重建仍然具有重要意义临床挑战。在世界范围内，自体移植物或同种异体移植物被用于大约 300 万例骨科手术每年进行手术，其中 6% 属于颅颌面手术。骨组织工程备受赞誉作为替代自体骨移植修复骨缺损的最终解决方案。然而，长期的成功工程结构的血管化不足阻碍了骨组织工程的发展。目前的组织工程支架血管化方面缺乏进展归因于我们的不完全理解骨修复和再生中的血管生成和血管床。功能性血管网络包括动脉、静脉和毛细血管接口，连接动脉和静脉微血管以实现适当的血管灌注。虽然动脉和静脉内皮的规格在早期已经得到了很好的研究胚胎发育、出生后动脉和静脉扩张的调节以及毛细血管的规范人们对修复和再生过程中的水平知之甚少。最近的一系列研究表明缺氧影响成骨和血管生成界面的内皮细胞（EC）规范发育和老化。缺氧诱导因子 1 (HIF-1) 通路的基因操作显着影响毛细血管特定子集的形成，称为 H 型 (CD31highEmcnhigh) 血管，在长骨干骺端与 OSX+ 成骨细胞结合。为了更好地理解其关键作用修复和再生过程中成骨和血管生成界面缺氧，我们建立了一系列新颖的允许对毛细血管进行高分辨率、定量和功能分析的成像方法与颅骨缺损部位的 Col (I) 2.3 GFP+ 成骨细胞偶联。利用这些新颖的成像方法通过逐层启用、纳米纤维介导的颅骨缺损修复模型，我们证明了成骨- 依赖性血管生成由形态和功能上不同的 CD31+Emcn+ 和 CD31+Emcn- 组成船只。血管类型分布和骨再生的检查表明存在差异血管生成反应和 CD31+Emcn+ 和 CD31+Emcn- 血管的对比分布 Col I (2.3) GFP+ 成骨细胞、新骨和非骨形成组织，表明 EC 规范毛细血管水平是骨修复和再生中成骨依赖性血管生成的关键组成部分。基于这些发现，我们建议检查缺氧对 EC 规格的影响以及颅骨缺损修复和再生过程中 EC 规范对骨形成的失调。三互补的目标将结合成像、遗传和工程方法来定义成骨- 依赖的 EC 规范以及缺氧在修复和再生中的作用。我们研究的成功将为修复中的成骨和血管生成机制提供新的见解，可能提供新的骨再生的转化目标。