Endothelial Function in Response to Topographical Micropatterning

内皮功能对地形微图案的反应

基本信息

批准号：
10535346
负责人：
Meghan Elizabeth Fallon
金额：
$ 4.68万
依托单位：
OREGON HEALTH & SCIENCE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-08-22 至 2025-08-21
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10535346
关键词：
Actins Adult Affect Anastomosis - action Anti-Inflammatory Agents Attenuated Autologous Transplantation Biocompatible Materials Biological Response Modifiers Blood Bypass Caliber Cardiovascular Diseases Cause of Death Cell Adhesion Molecules Cell Shape Cell physiology Cells Cellular Morphology Chronic Clinical Complex Cues Data Development Down-Regulation Endothelial Cells Endothelium Environment Equilibrium Exposure to Failure Functional disorder Gene Expression Gene Expression Profile Genes Genetic Transcription Goals Growth Hemostatic Agents Hemostatic function In Vitro Individual Inflammatory Intervention Liquid substance Mechanical Stress Mechanoreceptors Mediating Mediator of activation protein Microtubule Polymerization Microtubules Modification Morphology Pathway interactions Patient-Focused Outcomes Patients Pattern Phenotype Procedures Proteins Regulation Resistance Role Side Signal Pathway Surface TNF gene Techniques Technology Thrombosis Thrombus Tissue-Specific Gene Expression Tissues Transducers Up-Regulation Vascular Cell Adhesion Molecule-1 Vascular Endothelial Cell Vascular Graft Western Blotting Work biomaterial compatibility cell growth cytokine design graft function hemodynamics high risk immunogenic immunogenicity improved inflammatory milieu monolayer mortality novel protein activation protein expression response shear stress tool transcription factor transcriptome sequencing

项目摘要

Project Summary Cardiovascular disease affects nearly half of all U.S. adults and is the leading cause of death worldwide. Advanced cases are often treated through vascular grafting to bypass occluded vessels. Synthetic vasculargraft materials suffer from patency complications due to thrombosis and neointimal growth impeding the materials’ long-term function for small-diameter applications. Thus, there is a critical unmet need for improved biocompatible small-diameter vascular grafts in order to support long-term patient outcomes and reduce re- intervention procedures. The in vitro establishment of an endothelial layer on synthetic biomaterials has been suggested to be a solution due to the endothelial cells’ (ECs) homeostatic capabilities to prev ent thrombus formation and limit immunogenicity. Therefore, vascular graft material surfaces which support EC growth and function are a significant clinical need. ECs actively respond to both material surface cues and local hemodynamic fluid shear stress (FSS) to balance hemostasis, immuno-protection, and thrombo-resistance via a variety of mechano-receptors and -transducers. While unidirectional FSS induces morphological whole cell elongation and alignment as well as alignment of cytoskeletal components, oscillatory FSS (located at end-to- side anastomoses of vascular grafts) induces a cobblestoneEC morphology with randomcytoskeletal alignment. Krüppel-like factor 2 (KLF2) and Yes-associated protein (YAP) are transcription factors that are highly sensitive to cell shape and mechanical stresses. KLF2 and YAP have been shown to regulate EC function and phenotype. KLF2 is upregulated under unidirectional FSS, resulting in an anti-inflammatory phenotype. YAP is hyper- activated under oscillatory FSS and induces an immuno-prone phenotype, while remaining inactivated under unidirectional FSS. However, in the absence of FSS, the role of transcription factor regulation in EC morphology and cytoskeletal alignment driven immuno-protection is unknown. EC morphology and cytoskeletal alignment can be controlled using techniques of topographical micropatterning, independent of hemodynamic flow. We and others have shown that topographical micropatterning drivesan anti-inflammatory EC phenotypein static culture, making it a promising tool for synthetic graft surfaces. Studies of micropatterned ECs have shown additive benefits of patterning to unidirectional FSS and the ability to maintain cellular elongation under orthogonal unidirectional flow. This suggests that ECs on micropatterned surfaces may be more resistant to the immunogenic effects of oscillatory flow; yet this has never been directly studied. The proposed work aims to (1) elucidate the mechanism by which transcription factors regulate endothelial morphology driven functions independent of hemodynamic effects and (2) determine the effect of oscillatory flow on micropatterned EC transcription factor regulation and immunogenicity. Determining how ECs respond to topographical micropatterning is critical in designing improved synthetic vascular grafts for small-diameter applications.

项目概要心血管疾病影响着近一半的美国成年人，是全球死亡的主要原因。晚期病例通常通过血管移植来绕过闭塞血管进行治疗。由于血栓形成和新内膜生长阻碍材料的使用，材料会出现通畅并发症。因此，迫切需要改进小直径应用的长期功能。生物相容性小直径血管移植物，以支持患者的长期治疗效果并减少复发合成生物材料上的内皮层的体外建立已被证实。由于内皮细胞 (EC) 具有预防血栓的稳态能力，因此被认为是一种解决方案因此，血管移植材料表面支持 EC 生长和限制免疫原性。功能是重要的临床需求。血流动力学流体剪切应力（FSS）通过平衡止血、免疫保护和抗血栓性而单向 FSS 则诱导形态学全细胞。伸长和对齐以及细胞骨架成分的对齐，振荡 FSS（位于端对端）血管移植物的侧吻合）诱导具有随机细胞骨架排列的鹅卵石 EC 形态。 Krüppel 样因子 2 (KLF2) 和 Yes 相关蛋白 (YAP) 是高度敏感的转录因子 KLF2 和 YAP 已被证明可以调节 EC 功能和表型。 KLF2 在单向 FSS 下上调，导致 YAP 具有高抗炎表型。在振荡 FSS 下激活并诱导免疫倾向表型，同时在振荡 FSS 下保持失活然而，在缺乏 FSS 的情况下，转录因子调控在 EC 形态中的作用细胞骨架排列驱动的免疫保护尚不清楚。可以使用地形微图案技术进行控制，与血流动力学无关。其他人已经表明，地形微图案驱动抗炎 EC 表型静态培养，微图案 EC 的研究表明它是一种有前途的合成移植表面工具。单向 FSS 图案化的好处以及在正交条件下保持细胞伸长的能力这表明微图案表面上的 EC 可能更能抵抗单向流动。振荡流的免疫原性效应；然而，这项工作的目的是（1）。阐明转录因子调节内皮形态驱动功能的机制独立于血流动力学效应，并且 (2) 确定振荡流对微图案 EC 的影响确定 ECs 对地形的反应。微图案化对于设计用于小直径应用的改进的合成血管移植物至关重要。