Biophysical regulation of macrophage function

项目总结 巨噬细胞是创伤后炎症和组织愈合的中枢调节细胞 感染，以及在疾病期间。虽然很多人都知道如何溶解，但生物化学因素在 环境调节巨噬细胞功能，对生物物理信号如何调节知之甚少 它们的反应，尽管这些细胞存在于固体组织中，这些组织富含机械 暗示。此外，许多巨噬细胞参与的疾病，如癌症和 纤维化，以组织生物物理性质的变化为特征。我们之前的工作 证明黏附于软细胞外基质水凝胶可抑制巨噬细胞 炎性激活。在前期工作中，我们发现基质的刚性影响 YAP是一种转录辅助因子，参与细胞增殖、器官大小控制和 癌症，但在巨噬细胞激活中具有先前未被描述的作用。粘合到僵硬 底物导致YAP核定位，这似乎为巨噬细胞提供了强大的 炎症反应。此外，细胞骨架聚合和机械活化 和钙离子通道Piezo1似乎参与了YAP核的定位和 炎性激活。在这项研究中，我们建议研究分子机制。 不同硬度的巨噬细胞反应中的YAP信号和Piezo1活性 环境。在目标1中，我们将研究僵硬对细胞骨架重塑和 YAP活性的相关信号通路。在目标2中，我们将探讨Piezo1介导的作用 钙在僵硬感觉、YAP信号和巨噬细胞功能中的活性。最后，在目标3中， 我们将在体内研究YAP和Piezo1在巨噬细胞介导的伤口愈合中的作用 使用的是小鼠皮下生物材料植入模型。一个改进的基本原理 了解巨噬细胞如何感知其机械环境可能会带来新的 疾病期间控制巨噬细胞功能的免疫调节策略。

PROJECT SUMMARY Macrophages are central regulators of inflammation and tissue healing following injury or infection, and during disease. While much is known about how soluble, biochemical factors in the environment regulate macrophage function, less is known about how biophysical cues regulate their response, despite the fact that these cells exist within solid tissues that are rich in mechanical cues. Furthermore, many diseases in which macrophages are involved, such as cancer and fibrosis, are characterized by changes in tissue biophysical properties. Our previous work demonstrated that adhesion to soft extracellular matrix hydrogels inhibits macrophage inflammatory activation. In preliminary work, we found that matrix rigidity influences the localization of YAP, a transcriptional co-factor involved in cell proliferation, organ size control, and cancer, but with previously undescribed role in macrophage activation. Adhesion to stiff substrates leads to YAP nuclear localization, which appears to prime macrophages for a potent inflammatory response. In addition, cytoskeletal polymerization and the mechanically-activated and calcium-permeable ion channel Piezo1 appear to be involved in YAP nuclear localization and inflammatory activation. In this study, we propose to investigate the molecular mechanisms underlying YAP signaling and Piezo1 activity in the macrophage response within different stiffness environments. In Aim 1, we will examine the effect of stiffness on cytoskeletal remodeling and associated signaling pathways on YAP activity. In Aim 2, we will probe the role of Piezo1-mediated calcium activity in stiffness sensing, YAP signaling, and macrophage function. Finally, in Aim 3, we will investigate the role of YAP and Piezo1 on macrophage-mediated wound healing in vivo using a murine subcutaneous biomaterial implant model. An improved fundamental understanding of how macrophages sense their mechanical environment may lead to new immunomodulatory strategies that control macrophage function during disease.