Aligned Tendon or Ligament Derived Matrix Nanoscaffolds for Rotator Cuff Repair

用于肩袖修复的对齐肌腱或韧带衍生基质纳米支架

• 批准号: 8111496
• 负责人: Dianne Little
• 金额: $ 9.8万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-04 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8111496
• 关键词: Adipose tissue; Animal Model; Anisotropy; Architecture; Award; Basic Science; Biochemical; Biological Assay; Biomechanics; Biomedical Engineering; Cells; Chronic; Clinical; Collagen; Collagen Fiber; Collection; Confocal Microscopy; Consultations; DNA; Data; Deposition; Development; Devices; Disease; Doctor of Philosophy; Educational process of instructing; Environment; Equipment; Extracellular Matrix; Failure; Fiber; Fourier Transform; Gastrointestinal Physiology; Gene Expression; Goals; Human; Image; In Vitro; Infiltration; Inflammation; Joint Capsule; Laboratory Research; Left; Ligaments; Manuscripts; Measures; Mechanics; Mentorship; Modification; Muscle; Nuclear; Operative Surgical Procedures; Orthopedics; Phenotype; Porosity; Positioning Attribute; Process; Property; Proteoglycan; Publishing; Reporting; Research; Research Personnel; Research Project Grants; Research Training; Resistance; Rodent Model; Rotator Cuff; Scanning Electron Microscopy; Shapes; Shoulder; Solid; Solutions; Stem cells; Stress; Stress Tests; Structure; Surface; Surgeon; Surgical sutures; Tenascin; Tendon structure; Testing; Time; Tissue Engineering; Tissues; Training; Work; aqueous; biglycan; biomaterial compatibility; biomaterial development; bone; career; career development; cell motility; decorin; electric field; experience; in vivo; injury and repair; innovation; meetings; nanofiber; novel; novel strategies; polysulfated glycosaminoglycan; post-doctoral training; repaired; responsible research conduct; scaffold; scleraxis; skills; standard care; standard of care; statistics; success

DESCRIPTION (provided by applicant): Candidate: The candidate is a board-certified veterinary surgeon with extensive research training in animal models and basic science who transitioned after earning a PhD in gastrointestinal physiology to postdoctoral training in biomedical engineering. Her immediate career development goals in the current proposal will be in biomechanics and tissue engineering and will allow expansion of current skills in mechanical testing and stress-strain analysis, biomaterial development, confocal microscopy, image and data post-processing and fast Fourier transform analysis, skills essential to the success of the research project and long term career goals as an independent investigator in the field of tendon and ligament tissue engineering. The candidate plans R03 submission in year 2 to evaluate biocompatibility of the proposed scaffolds in rodent models, and then an R01 submission in year 4 to evaluate the proposed scaffolds in a large animal model of chronic rotator cuff tear, and expects to publish three manuscripts resulting from this initial work. Additional didactic training in tissue engineering, statistics and responsible conduct of research will be obtained during the award period. Environment: The mentorship of Dr. Farshid Guilak PhD and co-mentorship of Dr. David Ruch MD, combined with the degree of institutional commitment will provide this candidate with the support needed to transition successfully into an independent research career. External consultation from experts in rotator cuff disease, research and repair will provide added expertise. All the equipment and facilities needed by the candidate for successful completion of this proposal are already available in the Orthopaedic Research Laboratories in the Department of Surgery, and the candidate has 100% protected time, with no administrative, clinical or teaching responsibilities to allow for the successful completion of this project. Research: The rotator cuff is a composite of joint capsule, tendons and ligaments that is critical for stability and function of the shoulder. There are over 300,000 rotator cuff injuries repaired annually in the US, at an annual burden in surgical expenses alone of $3-4 billion. Suture repair is the clinical standard of care but re- tear rates of 34-94% have been reported. Extracellular matrix (ECM) scaffolds are used for augmentation of rotator cuff repair because they contain bioactive molecules that stimulate cell migration, proliferation and ECM synthesis. All of the currently available ECM scaffold patches used to augment suture repair have limitations and none mimic the interdigitating multi-layered structure of the normal rotator cuff which has layers of collagen aligned at 45 degrees to each other to allow efficient load transfer and distribution, suture retention and resistance to failure. Therefore, there is a need for a rotator cuff patch that meets all of the deficiencies of currently available devices, while retaining the benefits of using ECM. The long term goal of the proposed research is to develop a tendon or ligament derived-extracellular matrix (TLDM) patch for augmentation of rotator cuff repair or as a tendon substitute in irreparable rotator cuff tears while allowing the PI to establish an independent research career in tissue engineering of tendon and ligament. Electrospun nanofibers are attractive for tissue engineering of a rotator cuff patch because the fibers can be aligned to mimic the natural architecture and biomechanical properties of native tissue. Electrospinning into an aqueous solution and collection of multiple layers of scaffold (hydrospinning) increases porosity and further enhances cell infiltration compared to more traditional nanoscaffolds deposited as a single layer onto a solid ground plate. We have shown that a novel TLDM enhances proliferation and early differentiation of human adipose stem cells (hASCs) towards a tendon phenotype and that TLDM can be used to produce hydrospun nanofiber scaffolds. We have developed a novel strategy to align adjacent layers of hydrospun nanofibers in different directions by modification of the shape of the electric field. The PI is well prepared to meet the scientific and training goals of this application through the research experience already acquired in the proposed research and mentorship environment, and through the mentorship and continued development in this environment covered in this proposal. The overall hypothesis is that aligned TLDM scaffolds will show anisotropic ECM maturation compared to non-aligned scaffolds, and scaffolds with layers aligned at 45 degrees to each other (45-Offset) will demonstrate increased mechanical properties over a range of load directions than TLDM scaffolds with all layers aligned similarly (0- Offset) or non-aligned TLDM scaffolds. Use of 45-Offset layers of hydrospun fibers represents an innovative approach to promote early ECM synthesis, alignment and maturation in a multi-layered RC tendon TLDM patch. We will test the following hypotheses: Hypothesis 1: Scaffold fiber alignment and mechanical anisotropy will be greatest in 0-Offset scaffolds followed by 45-Offset scaffolds and finally non-aligned TLDM scaffolds. Hypothesis 2: 45-Offset and 0-Offset scaffolds will show increased cell and ECM alignment and maturation when seeded with hASCs, compared to non-aligned scaffolds. We expect that 45-Offset aligned TLDM scaffolds will permit earlier and more aligned ECM synthesis and maturation compared to non-aligned scaffolds and reduced mechanical anisotropy compared to 0-Offset aligned scaffolds.

描述（由申请人提供）： 候选人：候选人是一名经过委员会认证的兽医，在动物模型和基础科学方面接受过广泛的研究培训，在获得胃肠生理学博士学位后转入生物医学工程博士后培训。她在当前提案中的直接职业发展目标将是生物力学和组织工程，并将允许扩展机械测试和应力应变分析、生物材料开发、共焦显微镜、图像和数据后处理以及快速傅立叶变换分析方面的当前技能，作为肌腱和韧带组织工程领域的独立研究者，对于研究项目的成功和长期职业目标至关重要的技能。候选人计划在第 2 年提交 R03，以评估啮齿动物模型中拟议支架的生物相容性，然后在第 4 年提交 R01，以评估慢性肩袖撕裂大型动物模型中的拟议支架，并预计发表三份手稿从这个最初的工作开始。获奖期间将获得组织工程、统计学和负责任的研究行为方面的额外教学培训。环境：Farshid Guilak 博士的指导和 David Ruch 博士的共同指导，加上机构的承诺程度，将为该候选人提供成功过渡到独立研究职业所需的支持。肩袖疾病、研究和修复专家的外部咨询将提供额外的专业知识。候选人成功完成本提案所需的所有设备和设施均已在外科部骨科研究实验室中提供，并且候选人拥有 100% 的受保护时间，无需承担任何行政、临床或教学责任。该项目的顺利完成。研究：肩袖是由关节囊、肌腱和韧带组成的复合体，对于肩部的稳定性和功能至关重要。美国每年修复超过 30 万例肩袖损伤，每年仅手术费用就高达 3-40 亿美元。缝线修复是临床护理标准，但据报道，再撕裂率为 34-94%。细胞外基质 (ECM) 支架用于增强肩袖修复，因为它们含有刺激细胞迁移、增殖和 ECM 合成的生物活性分子。目前用于增强缝合修复的所有 ECM 支架补片均存在局限性，并且没有一个能够模仿正常肩袖的叉指多层结构，该结构具有彼此成 45 度对齐的胶原层，以实现有效的负载转移和分布、缝合保持力和抗失败能力。因此，需要一种肩袖补片，能够满足当前可用装置的所有缺陷，同时保留使用 ECM 的优点。拟议研究的长期目标是开发肌腱或韧带衍生的细胞外基质（TLDM）补片，以增强肩袖修复或作为不可修复的肩袖撕裂的肌腱替代品，同时允许 PI 在以下领域建立独立的研究生涯：肌腱和韧带的组织工程。电纺纳米纤维对于肩袖补片的组织工程很有吸引力，因为纤维可以排列以模仿天然组织的自然结构和生物力学特性。与作为单层沉积在固体接地板上的更传统的纳米支架相比，静电纺丝到水溶液中并收集多层支架（水纺）可增加孔隙率并进一步增强细胞渗透。我们已经证明，一种新型 TLDM 可以增强人类脂肪干细胞 (hASC) 向肌腱表型的增殖和早期分化，并且 TLDM 可用于生产水纺纳米纤维支架。我们开发了一种新颖的策略，通过改变电场的形状，在不同方向上排列相邻的水纺纳米纤维层。通过在拟议的研究和指导环境中已经获得的研究经验，以及通过本提案中涵盖的该环境中的指导和持续发展，PI 已做好充分准备，可以实现本申请的科学和培训目标。总体假设是，与非对齐支架相比，对齐的 TLDM 支架将表现出各向异性 ECM 成熟，并且层彼此成 45 度对齐（45 偏移）的支架将在一系列负载方向上表现出比 TLDM 支架更高的机械性能所有层均以相似方式对齐（0 偏移）或不对齐 TLDM 支架。使用 45 偏移层水纺纤维代表了一种创新方法，可促进多层 RC 肌腱 TLDM 补片中的早期 ECM 合成、排列和成熟。我们将测试以下假设： 假设 1：支架纤维排列和机械各向异性在 0 偏移支架中最大，其次是 45 偏移支架，最后是非排列 TLDM 支架。假设 2：与未对齐的支架相比，当接种 hASC 时，45 偏移和 0 偏移支架将显示出更高的细胞和 ECM 对齐和成熟度。我们预计，与非对齐支架相比，45 偏移对齐的 TLDM 支架将允许更早、更对齐的 ECM 合成和成熟，并与 0 偏移对齐支架相比，减少机械各向异性。