Microphysiological Models to Evaluate the Role of Age-Dependent Fibrinogen Sialylation in Wound Healing

评估年龄依赖性纤维蛋白原唾液酸化在伤口愈合中作用的微生理学模型

• 批准号: 2211404
• 负责人: Ashley Brown
• 金额: $ 50.88万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2211404&HistoricalAwards=false
• 关键词: Microphysiological; Models; Evaluate; Role; Age

Wound healing is a complex process. The first step in wound healing is clotting. The clot that forms stops bleeding and provides support for cells to rebuild damaged tissue. Wound healing is also different between babies and adults, but these differences are not well understood. This project will develop new tools to better understand (1) how clotting is different between babies and adults and (2) how differences in clotting lead to differences in wound healing. Many cells types are involved in healing, including platelets and fibroblasts. Platelets play important roles in clotting and fibroblasts help rebuild damaged tissue after bleeding stops. The project will also measure interactions between fibroblasts and platelets in wound healing. Better understanding of wound healing is expected to lead to identification of novel therapeutic targets for the nearly 6 million people in the United States suffering from impaired coagulation and non-healing wounds. The project's education component involves training undergraduate and graduate students in engineering biomedical systems, including working with clinicians. Outreach activities include developing hands-on educational modules and activities that will be innovated for K-12 science fair competitions and constructing a demonstration kit for the Annual College of Veterinary Medicine Open House Day and the North Carolina Science Café, which engages K-12 students in the region. Wound healing involves the complex orchestration of biochemical and mechanical signals directing behavior of multiple cell types. Due to the complex nature of wound healing, much remains unknown about mechanisms underlying impaired healing. After injury, a fibrin clot is formed that stops bleeding and promotes healing by serving as a provisional scaffold for infiltrating cells that support tissue repair. A deficient fibrin matrix can result in non-healing wounds. While it is known that aging influences healing, it is unknown how age related differences in fibrin properties may influence healing outcomes. Recent studies have identified extensive differences in fibrin network properties between adults and neonates. For example, fibroblasts attach and migrate better on neonatal fibrin compared to adult fibrin, and neonatal fibrin scaffolds promote better healing in vivo in a murine full thickness injury model compared to adult fibrin scaffolds. While many variances in post-translational modifications likely contribute to age-related differences in fibrinogen function, recent data highlights that increased sialic acid (Sia) content in neonatal fibrinogen contributes significantly to age-related differences in clot structure, mechanics, and polymerization and degradation dynamics. The overarching hypothesis of this work is that increased Sia content in neonatal fibrinogen results in altered fibrin polymerization mechanisms, clot structure, and mechanical properties compared to adult fibrinogen, which drives improved healing outcomes. This project will investigate how Sia content in neonatal and adult fibrinogen networks +/- Sia influence adult and neonatal fibroblast responses in vitro. Next, this project will investigate how Sia content influences cellular crosstalk in wound healing. Innovative tissue engineering techniques and microfluidics will be employed to develop a microphysiological system (MPS) to study the interactions of platelets and fibroblasts during wound healing. MPS provide a means to generate actionable, translatable data by recapitulating select human tissue functions with the requisite primary human cell types, microanatomy, cell-cell interactions and micromechanical cues.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

伤口愈合是一个复杂的过程，形成的凝块可以止血并为细胞重建受损组织提供支持，但这些差异尚不清楚。该项目将开发新工具，以更好地了解（1）婴儿和成人之间的凝血有何不同，以及（2）凝血的差异如何导致伤口愈合的差异，包括血小板和成纤维细胞。中的重要角色凝血和成纤维细胞有助于在出血停止后重建受损组织。该项目还将测量伤口愈合过程中成纤维细胞和血小板之间的相互作用，预计将为美国近 600 万人确定新的治疗靶点。该项目的教育部分涉及对工程生物医学系统的本科生和研究生进行培训，包括与精英合作开发实践教育模块和创新活动。 K-12 科学博览会竞赛以及为年度兽医学院开放日和北卡罗来纳州科学咖啡馆构建演示套件，吸引该地区的 K-12 学生进行伤口愈合，涉及指导生化和机械信号的复杂编排。由于伤口愈合的复杂性，损伤后形成的纤维蛋白凝块可以作为浸润的临时支架来止血并促进愈合。支持组织修复的细胞。缺乏纤维蛋白基质会导致伤口无法愈合。虽然众所周知，衰老会影响愈合，但目前尚不清楚与年龄相关的纤维蛋白特性差异如何影响愈合结果。例如，与成人纤维蛋白相比，成纤维细胞在新生儿纤维蛋白上更好地附着和迁移，并且与成人相比，新生儿纤维蛋白支架在小鼠全层损伤模型中促进更好的体内愈合。虽然翻译后修饰的许多差异可能导致纤维蛋白原功能的年龄相关差异，但最近的数据强调，新生儿纤维蛋白原中唾液酸（Sia）含量的增加显着导致了血栓结构、力学和功能的年龄相关差异。这项工作的总体假设是，与成人相比，新生儿纤维蛋白原中 Sia 含量的增加会导致纤维蛋白聚合机制、凝块结构和机械特性的改变。该项目将研究新生儿和成人纤维蛋白原网络中的 Sia 含量如何影响成人和新生儿成纤维细胞反应。接下来，该项目将研究 Sia 含量如何影响伤口愈合中的细胞串扰。将采用创新的组织工程技术和微流体技术来开发微生理系统（MPS），以研究伤口愈合过程中血小板和成纤维细胞的相互作用，MPS 提供了一种产生可操作的、可操作的方法。通过使用必要的主要人类细胞类型、显微解剖学、细胞间相互作用和微机械线索来概括选定的人体组织功能，从而获得可翻译的数据。该奖项反映了法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。