CAREER: Engineering Extracellular Matrix Ligands for Macrophage Control

巨噬细胞是一种免疫细胞，可以通过采用促炎（坏）到促组织愈合（好）的功能状态来指导伤口愈合。巨噬细胞接收来自环境/细胞外基质（ECM）的信号以改变其功能状态。ECM指导巨噬细胞功能的方法之一是通过整合素。整合素是在巨噬细胞膜上发现的受体，它们的相关配体（可以与受体结合的分子）遍布整个ECM。ECM整合素受体-配体对可以决定巨噬细胞的功能状态。目前，了解ECM配体和巨噬细胞整合素受体之间基本关系的策略有限。在这个CAREER项目中，研究者将结合ECM配体和肽聚合物化学来设计生物材料工具，以研究ECM配体对巨噬细胞功能的影响。该计划将通过引入生物材料工具来量化ECM配体的影响，从而增加对ECM配体如何影响巨噬细胞功能的基本理解。教育和推广活动与拟议的研究相结合，包括为本科生介绍生物材料商业项目计划，为历史上被排斥的学生开发生物材料职业机会研讨会，并为中学生扩展生物材料项目。巨噬细胞免疫细胞通过其微环境的信号决定组织稳态、伤口愈合和组织再生。研究者的长期研究目标是了解细胞外基质（ECM）成分如何指导巨噬细胞的功能。为了支持这一目标，本CAREER项目专注于开发基于聚乙二醇的生物材料工具，该工具具有已知肽衍生的ECM配体，以量化整合素配体受体对巨噬细胞活化的影响。虽然我们已经了解了一些线索如何指导巨噬细胞的功能，但作为一个领域，我们还不清楚细胞外基质（ECM）如何指导巨噬细胞的功能。由于缺乏对ECM配体掺入的控制，设计用于研究巨噬细胞在ECM中的功能的现有实验系统受到限制。本项目开发的工具将克服这一限制。研究旨在验证中心假设，即ecm衍生的胶原、层粘连蛋白和纤维连接蛋白配体将巨噬细胞激活引导至促炎症状态或促组织愈合状态。利用聚合物化学和已知的ECM配体，提出的工作包括三个研究目标：1)通过三维肽筛选量化整合素配体对巨噬细胞功能的影响；2)设计组合ECM配体生物材料，量化ECM生态位对巨噬细胞功能的影响；3)通过组合ECM配体生物材料量化年龄对人供体巨噬细胞功能的影响。为了成功完成这些目标，研究者实验室建立的技术将用于聚合物肽偶联、水凝胶配方、机械评估和三维生物材料中巨噬细胞的可溶性刺激。巨噬细胞功能的分子评估将包括分泌组分析、免疫细胞化学以及与每个ECM配体相互作用导致的基因表达改变的询问。完成上述任务将为理解ECM配体如何通过设计生物材料工具来指导巨噬细胞的功能奠定基础。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Macrophages are immune cells that can direct wound healing by adopting functional states that range from pro-inflammatory (bad) to pro-tissue healing (good). To change their functional state, macrophages receive signals from their environment/extracellular matrix (ECM). One of the ways the ECM can direct macrophage function is through integrins. Integrins are receptors found on macrophage membranes, and their associated ligands (molecules that can bind to the receptors) are found throughout the ECM. The ECM integrin receptor-ligand pair can determine the macrophage functional state. Currently, there are limited strategies to understand the fundamental relationship between ECM ligands and macrophage integrin receptors. In this CAREER project, the investigator will combine ECM ligands with peptide polymer chemistry to design biomaterial tools for investigating the influence of ECM ligands on macrophage function. The proposed program will increase fundamental understanding of how ECM ligands inform macrophage function by introducing biomaterial tools to quantify ECM ligand influence. Education and outreach activities are integrated with the proposed research and involve introducing a biomaterials business project plan for undergraduate students, developing a workshop for biomaterial career exposure to historically excluded students, and extending biomaterial projects for middle school students.Macrophage immune cells determine tissue homeostasis, wound healing, and tissue regeneration through signals from their microenvironment. The investigator’s long-term research goal is to understand how extracellular matrix (ECM) composition directs macrophage function. In support of this goal, this CAREER project focuses on developing polyethylene glycol-based biomaterial tools with known peptide-derived ECM ligands to quantify integrin ligand-receptor influence on macrophage activation. While it is understood how some cues direct macrophage function, as a field it is not understood how the extracellular matrix (ECM) directs macrophage function. Existing experimental systems designed to investigate macrophage function in the ECM are limited due to lack of control over incorporation of ECM ligands. The tools developed in this project will overcome this limitation. Studies are designed to test the central hypothesis that ECM-derived ligands from collagen, laminin, and fibronectin direct macrophage activation either towards a pro-inflammatory state or towards a pro-tissue healing state. Leveraging polymer chemistry and known ECM ligands, the proposed work comprises three research objectives: 1) quantifying integrin ligands influence on macrophage function via three-dimensional peptide screening, 2) designing combinatorial ECM ligand biomaterials to quantify ECM niche impact on macrophage function; and 3) quantifying the influence of age on human-donor macrophage function via combinatorial ECM ligand biomaterials. To successfully complete these aims, techniques established in the investigator’s lab will be employed for polymer-peptide conjugation, hydrogel formulation, mechanical assessments, and soluble stimulation of macrophages in a three-dimensional biomaterial. Molecular evaluations of macrophage function will include secretome analysis, immunocytochemistry, and interrogation of genetic expression alterations as a result of interaction with each ECM ligand. Completion of the tasks set forth will lay the foundation understanding how ECM ligands direct macrophage function through design of biomaterial tools.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.