Biophysical regulation of macrophage function

项目摘要 巨噬细胞是损伤后炎症和组织愈合的中枢调节因子， 感染和疾病期间。虽然我们对可溶性的生物化学因素有很多了解， 环境调节巨噬细胞功能，但对生物物理信号如何调节巨噬细胞功能知之甚少。 它们的反应，尽管这些细胞存在于固体组织中， 线索此外，巨噬细胞参与的许多疾病，如癌症和癌症， 纤维化的特征在于组织生物物理性质的变化。我们以前的工作 表明粘附到软的细胞外基质水凝胶抑制巨噬细胞 炎症激活在初步工作中，我们发现，矩阵刚度影响 雅普的定位，YAP是一种参与细胞增殖、器官大小控制和 癌症，但在巨噬细胞活化中具有先前未描述的作用。与硬组织的粘附 底物导致雅普核定位，这似乎使巨噬细胞产生有效的 炎症反应。此外，细胞骨架聚合和机械活化的 和钙渗透性离子通道Piezo1似乎参与雅普核定位， 炎症激活在这项研究中，我们建议调查的分子机制， 不同硬度下巨噬细胞反应中潜在的雅普信号传导和Piezo1活性 环境.在目标1中，我们将研究刚度对细胞骨架重塑的影响， 相关信号通路对雅普活性的影响。在目标2中，我们将探讨Piezo 1介导的 僵硬感测、雅普信号传导和巨噬细胞功能中的钙活性。最后，在目标3中， 我们将研究雅普和Piezo 1在体内巨噬细胞介导的伤口愈合中的作用 使用小鼠皮下生物材料植入模型。改进的基本 了解巨噬细胞如何感知它们的机械环境可能会导致新的 免疫调节策略，控制疾病期间巨噬细胞的功能。

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.