CAREER: Engineering Extracellular Matrix Ligands for Macrophage Control

巨噬细胞是一种免疫细胞，可以通过采用从促炎(BAD)到促组织愈合(GOOD)的各种功能状态来指导伤口愈合。为了改变其功能状态，巨噬细胞从其环境/细胞外基质(ECM)接收信号。细胞外基质引导巨噬细胞功能的方法之一是通过整合素。整合素是巨噬细胞膜上的受体，其相关的配体(可与受体结合的分子)在整个ECM中都能找到。细胞外基质整合素受体-配体对可以决定巨噬细胞的功能状态。目前，了解细胞外基质配体和巨噬细胞整合素受体之间的基本关系的策略有限。在这个职业项目中，研究人员将把细胞外基质配体与多肽聚合物化学结合起来，设计生物材料工具，研究细胞外基质配体对巨噬细胞功能的影响。拟议的计划将通过引入生物材料工具来量化细胞外基质配体的影响，从而增加对细胞外基质配体如何影响巨噬细胞功能的基本了解。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，为历史上被排除在外的学生开发生物材料职业暴露研讨会，以及为中学生扩展生物材料项目。巨噬细胞免疫细胞通过来自其微环境的信号来确定组织动态平衡、伤口愈合和组织再生。研究人员的长期研究目标是了解细胞外基质(ECM)的组成如何指导巨噬细胞的功能。为了支持这一目标，这个职业项目专注于开发基于聚乙二醇基的生物材料工具，利用已知的多肽衍生的ECM配体来量化整合素配体-受体对巨噬细胞激活的影响。虽然已经知道一些信号如何引导巨噬细胞的功能，但作为一个领域，还不知道细胞外基质(ECM)如何引导巨噬细胞的功能。由于缺乏对ECM配体掺入的控制，现有的用于研究ECM中巨噬细胞功能的实验系统是有限的。本项目中开发的工具将克服这一限制。研究旨在验证这一中心假设，即来自胶原、层粘连蛋白和纤维连接蛋白的ECM配体引导巨噬细胞激活，要么朝着促炎状态，要么朝着有利于组织愈合的状态。利用聚合物化学和已知的ECM配体，建议的工作包括三个研究目标：1)通过三维肽筛选来量化整合素配体对巨噬细胞功能的影响；2)设计组合ECM配体生物材料来量化ECM对巨噬细胞功能的生态位影响；以及3)通过组合ECM配体生物材料来量化年龄对人-供体巨噬细胞功能的影响。为了成功地实现这些目标，研究人员实验室中建立的技术将用于聚合物-多肽结合、水凝胶配方、机械评估和三维生物材料中巨噬细胞的溶解刺激。巨噬细胞功能的分子评估将包括分泌组分析、免疫细胞化学和询问由于与每个ECM配体相互作用而导致的基因表达变化。完成规定的任务将为了解ECM配体如何通过生物材料工具的设计引导巨噬细胞的功能奠定基础。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.