Defining the Role of Type III Collagen in Neonatal Tendon Development and Healing

定义 III 型胶原蛋白在新生儿肌腱发育和愈合中的作用

• 批准号: 10605477
• 负责人: Margaret Kathryn Tamburro
• 金额: $ 4.77万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-07 至 2025-12-06
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10605477
• 关键词: Acceleration; Adult; Aging; Biology; Blood Vessels; Cells; Cellular Infiltration; Cellularity; Characteristics; Cicatrix; Clinical; Collagen; Collagen Fiber; Collagen Fibril; Collagen Type I; Collagen Type III; Deposition; Development; Developmental Process; Diameter; Dryness; Economic Burden; Ehlers-Danlos Syndrome; Environment; Extracellular Matrix; Fibroblasts; Foundations; Gene Expression; Glean; Growth; Immunohistochemistry; Incidence; Infiltration; Injury; Integrins; Investigation; Knock-out; Laboratory Research; Measures; Mechanics; Menopause; Minor; Modeling; Mus; Natural regeneration; Neonatal; Orthopedics; Pennsylvania; Perinatal; Phase; Play; Predisposition; Process; Property; Proteomics; Regulation; Reproducibility; Research Personnel; Resistance; Role; Scientific Inquiry; Smoking; Stress; Tendon Injuries; Tendon structure; Testing; Time; Tissue Engineering; Tissues; Training; Transmission Electron Microscopy; Universities; Weight; Work; clinically relevant; comparative; crosslink; defined contribution; density; fetal; fibrillogenesis; healing; improved; inflammatory milieu; injured; innovation; insight; joint mobilization; knock-down; mechanical properties; migration; mouse model; multidisciplinary; neonatal mice; neonate; novel; postnatal; postnatal development; prenatal; progenitor; recruit; regenerative; regenerative approach; response; response to injury; stem cells; tendon development; therapeutic target; viscoelasticity; wound healing

Project Abstract Tendons can withstand large forces due to a highly aligned, dense collagen matrix. However, their low cellularity and relative inability to recruit reparative cells post-injury, as well as susceptibility to excessive scarring, results in loss of tendon structure and mechanical function. Type I collagen (Col1) is the primary collagen of healthy tendon and type III collagen (Col3) is a minor constituent that increases in response to injury. Persistently increased Col3 contributes to persistent fibrovascular scarring and structural and functional deficits in the healing tendon. In perinatal tendons, Col3 is increased, similar to the injured state, compared to healthy mature tendons. Unlike the healing response, the process of neonatal tendon development yields a structurally and functionally superior tendon with a highly aligned Col1-dense matrix. Moreover, neonatal developing tendon demonstrates improved efficiency and quality of healing compared to healing mature tendon. Understanding the role of Col3 in the developmental and healing processes of the neonatal tendon will increase our ability to recapitulate tendon development with tissue engineering and improve tendon injury treatment. Therefore, our overall objective is to delineate the contribution of Col3 to development and healing in the neonatal tendon through modulation of matrix properties and cellular activity. Specifically, we will test the hypothesis that Col3 is crucial for early neonatal development but contributes less to regulation of development at later time points as relative Col3 in the tendon decreases. We also hypothesize that the neonatal tendon has enhanced capacity for a robust proliferative response to tendon injury which creates a Col3-dense healing matrix favorable for tendon progenitor migration and differentiation to ultimately deposit aligned, Col1 fibrils which restore tendon structure and function. To test these hypotheses, we generated a novel, inducible Col3 deficient mouse (i.e. Col3a1F/F) to temporally control Col3 reduction. The study aims are: Aim 1: Define the temporal dynamics of the regulatory function(s) of Col3 during phases of neonatal tendon development and Aim 2: Define the regulatory function(s) of Col3 during phases of neonatal healing. Viscoelastic mechanical testing, transmission electron microscopy, immunohistochemistry, gene expression, proteomics, and 11 integrin analyses will be used to assess the structural, mechanical, and compositional properties of tendons in both aims. Insights gleaned from this work will be relevant to a variety of conditions that reduce Col3 expression including vascular Ehlers Danlos syndrome, aging, smoking and menopause and will highlight therapeutic targets for enhancing tendon injury treatment. The proposed work will be carried out in a world- class training environment at the University of Pennsylvania’s McKay Orthopaedic Research Laboratory. This environment combined with an expert sponsorship team, including experts in studies of tendon structure and function as well as matrix biology, will fully support completion of this proposal and facilitate development into a competent independent investigator capable of producing rigorous and reproducible clinically relevant work.

项目摘要 由于高度排列，密集的胶原蛋白基质，肌腱可以承受大力。但是，他们的低点 细胞性和相对无法募集伤害后的修复细胞，以及对过量的敏感性 疤痕，导致肌腱结构和机械功能的丧失。 I型胶原蛋白（COL1）是主要的 健康肌腱和III型胶原蛋白（COL3）的胶原蛋白是一种较小的成分，可响应于 受伤。 Col3持续增加有助于持续的纤维血管疤痕以及结构和功能 愈合肌腱的缺陷。在围产期肌腱中，与受伤状态相似的Col3增加了 健康的成熟肌腱。与愈合反应不同，新生儿肌腱发育的过程产生了 在结构和功能上具有高度排列的COL1密度基质的肌腱。而且，新生儿 与愈合成熟相比 肌腱。了解Col3在新生儿肌腱的发展和康复过程中的作用 通过组织工程提高我们概括肌腱发育并改善肌腱损伤的能力 治疗。因此，我们的总体目标是描述Col3对开发和康复的贡献 在新生儿肌腱中，通过调节基质特性和细胞活性。具体来说，我们将测试 Col3对于早期新生儿发育至关重要的假设，但对发展的调控较少 在以后的时间点作为肌腱中的相对COL3下降。我们还假设新生儿肌腱具有 增强了对肌腱损伤的强大增生剂反应的能力，从而产生COL3密集的愈合 矩阵有利于肌腱祖细胞迁移和分化以最终排列的col1纤维 哪个还原肌腱结构和功能。为了检验这些假设，我们产生了一种新颖的，可诱导的Col3 缺乏小鼠（即COL3A1F/F）暂时控制COL3还原。研究目的是：目标1：定义 新生儿肌腱发育和 AIM 2：定义新生儿愈合阶段中Col3的调节功能。粘弹性机械 测试，透射电子显微镜，免疫组织化学，基因表达，蛋白质组学和11 整合素分析将用于评估肌腱在中的结构，机械和复合特性 两个目标。从这项工作中收集的洞察力将与减少Col3的各种条件有关 表达包括血管ihlers Danlos综合征，衰老，吸烟和更年期，将突出显示 用于增强肌腱损伤治疗的治疗靶标。拟议的工作将在世界上进行 - 宾夕法尼亚大学McKay骨科研究实验室的课堂培训环境。这 环境与专家赞助团队相结合，包括研究肌腱结构和研究专家 功能和矩阵生物学，将充分支持该提案的完成，并促进发展 能够生产严格且复制的临床相关工作的独立独立研究者。