The Mechanical Phenotype of Fetal Fibroblasts as a Model for Regenerative Repair

胎儿成纤维细胞的机械表型作为再生修复模型

• 批准号: 9024453
• 负责人: Aron Parekh
• 金额: $ 0.27万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-03-01 至 2016-04-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9024453
• 关键词: 3-Dimensional; Adhesions; Adult; Atomic Force Microscopy; Automobile Driving; Beds; Behavior; Biochemical; Biomechanics; Caring; Cells; Characteristics; Cicatrix; Clinical; Collagen; Collagen Type I; Collagen Type III; Contracts; Cues; Data; Defect; Deposition; Dermal; Disease; Environmental Risk Factor; Exhibits; Extracellular Matrix; Fetus; Fibroblasts; Fibrosis; Focal Adhesions; Gene Expression; Generations; Genetic Programming; Goals; Granulation Tissue; Harvest; Healed; Health; High-Throughput Nucleotide Sequencing; Human; Immunofluorescence Immunologic; In Vitro; Inflammation; Lead; Mechanical Stress; Mechanics; Medical; Modeling; Molecular; Molecular Target; Myofibroblast; Natural regeneration; Outcome; Pathologic; Pathology; Pathway interactions; Phenotype; Physiological; Play; Population; Property; RNA; Regenerative Medicine; Regenerative response; Research; Role; Sampling; Sequence Analysis; Signal Pathway; Skin; Smooth Muscle Actin Staining Method; Staging; Stress; Stress Fibers; Testing; Therapeutic; Tissue Engineering; Tissues; Traction; Transforming Growth Factors; Transplantation; Variant; Western Blotting; Work; Wound Healing; cost; design; fetal; healing; in vivo; injured; innovation; mRNA Expression; novel; programs; regenerative; repaired; response; tissue repair; transcriptome sequencing; treatment strategy; wound

 DESCRIPTION (provided by applicant): In post-natal or "adult" dermal wound healing, fibroblasts mechanically sense ("mechanosense") rigidity and tension that develop in granulation tissue and differentiate into myofibroblasts. Myofibroblasts generate large contractile forces that excessively contract and remodel the ECM resulting in scarring and fibrosis. In contrast, injured skin in the mammalian fetus heals scarlessly without myofibroblast involvement suggesting that smaller cellular forces contribute to regenerative repair. In vivo and in vitro studies have shown that fetal fibroblasts have unique characteristics that may contribute to scarless healing including altered responses to ECM rigidity and defective signaling pathways. However, it remains unclear why fetal fibroblasts retain this distinct phenotype and exhibit differential responses to environmental factors such as ECM rigidity that induce myofibroblast differentiation in adult fibroblasts. Therefore, our overall hypothesis is that fetal fibroblasts d not become myofibroblasts in response to physiologic biomechanical rigidities. We will test this hypothesis with the following Specific Aims: (1) to test the specific hypothesis that fetal fibroblasts have intrinsically altered mechanosensing which leads to ineffective myofibroblast differentiation, (2) to determine how matrix composition influences myofibroblast differentiation since adult and fetal wound healing are characterized by different types of collagen, and (3) to use a sequencing approach to identify molecular differences in fetal fibroblast gene expression that can be used to target myofibroblast differentiation in adult fibroblasts. We are taking an innovative approach by utilizing the mechanical phenotype of fetal fibroblasts as a model for understanding regenerative repair since these cells appear to lack the ability to produce larger cellular forces in response to matrix rigidity which contribute to myofibroblast differentiation an fibrotic healing. We will test our novel concept by using synthetic substrates that mimic the different mechanical stages of wound healing that progressively induce myofibroblast differentiation to isolate the effects of physiologic rigidities and different ECM components. Overall, our goal is to delineate the underlying molecular and physical mechanisms by which fetal fibroblasts differentially mechanosense ECM rigidity by quantifying cellular biomechanical properties relevant to dermal tissue repair. Furthermore, our research plan is designed to uncover potential molecular targets for novel treatment strategies for dermal scarring and fibrosis in post-natal wound healing. These studies are of particular clinical importance since no acceptable anti-fibrotic therapies currently exist and dermal scarring and fibrosis costs billions f dollars of year in medical care and management. In addition, the expected outcomes of our proposed studies are relevant to other fibrosis-related pathologies as well as to the fields of tissue engineering and regenerative medicine.

 描述（由适用提供）：在产后或“成人”皮肤伤口愈合中，成纤维细胞在机械上有意义（“机械”）刚性和张力在肉芽组织中发展并分化为肌纤维细胞。肌纤维细胞产生大收缩 极度收缩并重塑ECM的力导致疤痕和纤维化。相比之下，哺乳动物胎儿的受伤皮肤无毛治愈，而没有肌纤维细胞受累，这表明较小的细胞力有助于再生修复。体内和体外研究表明，胎儿成纤维细胞具有独特的特征，可能有助于无疤的愈合，包括对ECM刚性和缺陷信号通路的反应改变。但是，尚不清楚为什么胎儿成纤维细胞保留这种独特的表型，并暴露了对环境因素（例如ECM刚性）的差异反应，例如诱导成人成纤维细胞的肌纤维细胞分化。因此，我们的总体假设是，胎儿成纤维细胞d并不成为生理生物力学刚性的肌成纤维细胞。我们将以以下特定目的检验该假设：（1）测试以下特定假设：胎儿成纤维细胞具有内在改变的机制，导致无效的肌纤维细胞分化，（2）确定基质组成如何影响成年和胎儿伤口恢复的肌纤维细胞的差异，并在不同的类型中鉴定了摩尔菌的差异（3）。胎儿成纤维细胞基因表达，可用于靶向成年成纤维细胞中的肌纤维细胞分化。我们通过利用胎儿成纤维细胞的机械表型作为理解再生修复的模型来采用一种创新的方法，因为这些细胞似乎缺乏产生更大的细胞力来响应基质刚性的能力，从而导致成肌纤维细胞分化纤维化的愈合。我们将通过使用合成底物来测试我们的新概念，这些底物模仿伤口愈合的不同机械阶段，从而逐渐影响肌纤维细胞分化以隔离生理刚性和不同的ECM成分的作用。总体而言，我们的目标是描述胎儿成纤维细胞通过量化与真皮组织修复相关的细胞生物力学特性来差异机制ECM刚度的潜在分子和物理机制。此外，我们的研究计划旨在发现潜在的分子靶标，用于新的治疗策略，用于产后伤口愈合中的皮肤疤痕和纤维化。这些研究非常重要，因为目前没有可接受的抗纤维化疗法，并且皮肤疤痕和纤维化成本数十亿美元的医疗和管理中。此外，我们提出的研究的预期结果与其他与纤维化相关的病理以及组织工程和再生医学领域有关。