Studying Mechanotransduction in Late Embryonic Development to Inform Tendon Tissue Engineering

研究胚胎发育晚期的力转导为肌腱组织工程提供信息

基本信息

批准号：
9808374
负责人：
Spencer Szczesny
金额：
$ 18.81万
依托单位：
PENNSYLVANIA STATE UNIV HERSHEY MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-01 至 2021-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9808374
关键词：
Allogenic Area Autologous Automobile Driving Biocompatible Materials Biological Biological Products CRISPR/Cas technology Cell Volumes Cells Chick Embryo Chickens Collagen Fibril Computer Simulation Cues Development Disease Embryo Embryonic Development Engineering Event Experimental Models Failure Foundations Future Genes Harvest Human Image Imaging Techniques In Vitro Instruction Investigation Knock-out Knowledge Length Ligaments Mechanical Stimulation Mechanics Mediating Metatarsal bone structure Modulus Morbidity - disease rate Muscle Musculoskeletal Diseases PTK2 gene Pain Phase Property Protocols documentation Quality of life Rupture Signal Transduction Site Slide Stimulus Structure Techniques Tendon Injuries Tendon structure Testing Time Tissue Engineering Tissues Transplanted tissue United States Weight-Bearing state Work base cell behavior design disability disease transmission disorder risk extracellular falls hatching improved in vivo injured innovation knockout gene ligament injury mechanical drive mechanical load mechanical properties mechanotransduction novel prevent repaired response scaffold self assembly self organization tendon development tissue culture

项目摘要

Project Summary/Abstract Tendon and ligament injuries are a common cause of disability and pain. In many cases, the injured tissue cannot be repaired directly and must be replaced with a graft material. Ideally, a tissue engineered biomaterial could be used for this purpose; however, no tissue engineered construct has been successfully used to reconstruct human tendon or ligament ruptures. A primary reason for the failure in producing successful tendon replacements is that most tissue engineering approaches do not replicate normal tendon development. Scaffold-free techniques based on cellular self-assembly are able to generate tissues that that match the structure and mechanics of early embryonic tendon. However, they are unable to undergo a critical phase in late tendon development where the collagen fibrils elongate and fuse together generating a substantially stiffer and stronger material. One reason for this is that the constructs lacked the mechanical stimulation normally provided in vivo by muscles. In fact, chick embryo muscle activity peaks during late tendon development and this muscle activity is responsible for increasing the modulus of embryonic tendons. Nevertheless, while mechanical loading of constructs does improve tissue mechanics, they still fail to match the order-of-magnitude increase in mechanical properties observed in embryonic chick tendons. A critical barrier is the lack of knowledge regarding the mechanotransduction mechanisms that determine the cellular response to mechanical stimulation and drive late tendon development. Understanding how tendon cells respond to mechanical stimuli due to not only muscle loading but also the local changes in tissue structure and mechanics that occur during development is necessary to develop biomaterials that can successfully replicate tendon function. Therefore, the objective of this project is to identify the mechanotransduction mechanisms that mediate the multiscale changes in tissue structure and mechanics observed during late tendon development. Specifically, this project will (1) identify the multiscale structural and mechanical changes that occur during late tendon development and (2) determine the mechanotransduction mechanisms driving these changes. The overall hypothesis is that cells sense mechanical stimuli through a combination of cell-cell and cell-matrix interactions and that these mechanotransduction events are essential for driving proper tendon development. This will be evaluated by inhibiting embryonic muscle activity and perturbing mechanotransduction signaling in embryonic tendons via site-specific gene knockout during ex ovo culture of chicken embryos. The effects of these manipulations on tendon structure and mechanics will be determined by a novel combination of multiscale mechanical testing, computational modeling, and ultrastructural imaging. This work is the first investigation of the mechanotransduction mechanisms driving the structural and mechanical changes observed during late tendon development. The findings will provide the foundation for enhancing tissue engineered constructs to develop biomaterials that can successfully replace diseased tendons and ligaments.

项目摘要/摘要肌腱和韧带损伤是残疾和疼痛的常见原因。在许多情况下，受伤的组织不能直接维修，必须用移植物材料代替。理想情况下，组织工程生物材料可能是用于此目的；但是，没有成功地使用组织工程结构来重建人类肌腱或韧带破裂。未能产生成功肌腱替换的主要原因是大多数组织工程方法不会复制正常的肌腱发育。无脚手架技术基于细胞，自组装能够生成与早期结构和力学相匹配的组织胚胎肌腱。但是，他们无法在后期肌腱发育中经历关键阶段胶原原纤维伸长并融合在一起产生基本更硬，更强的材料。一个原因因为这是构造缺乏通常由肌肉在体内提供的机械刺激。实际上，小鸡胚胎肌肉活动在晚期发育期间达到峰值，这种肌肉活性是为了增加胚胎肌腱的模量。然而，虽然构造的机械加载确实改善组织力学，它们仍然无法匹配机械性能的刻度级增加在胚胎雏鸡肌腱中观察到。关键的障碍是缺乏有关确定细胞对机械刺激的细胞反应并驱动迟到的机械转导机制肌腱发育。了解肌腱细胞对机械刺激的反应如何，不仅是由于肌肉加载以及在开发过程中发生的组织结构和机械师的局部变化是必要的开发可以成功复制肌腱功能的生物材料。因此，这个项目的目的是确定介导组织结构多尺度变化和在肌腱发育后期观察到的力学。具体而言，该项目将（1）确定多尺度肌腱发育后期发生的结构和机械变化，（2）确定机械转导机制推动了这些变化。总体假设是细胞感知机械刺激通过细胞 - 细胞和细胞 - 矩阵相互作用的组合以及这些机械转移事件对于推动适当的肌腱发育至关重要。这将通过抑制胚胎肌肉来评估通过位点特异性基因敲除胚胎肌腱中的活性和扰动机械转导信号传导在鸡肉胚胎的卵子培养期间。这些操纵对肌腱结构和力学的影响将由多尺度机械测试，计算建模和超微结构成像。这项工作是对驱动机械转移机制的首次研究在晚期发育过程中观察到的结构和机械变化。这些发现将提供增强组织工程结构的基础，以开发可以成功替代的生物材料患病的肌腱和韧带。