Exosome-mediated Cooperative Mechanisms of Macrophage/Fibroblast Activation in Systemic Sclerosis

摘要 系统性硬化症（SSc）是一种病因不明的慢性自身免疫性疾病，其特征在于： 血管病变、纤维化和炎症。SSc无法治愈，FDA批准的疾病很少- 修改治疗。虽然成纤维细胞对疾病发展的贡献被广泛认可，但最近的研究表明， 研究表明巨噬细胞（MHP）也在SSc的发病机制中起作用。在最近出版的作品中， 我们开发了SSc MSTs的免疫表型谱，并证明MSTs与SSc的共培养 真皮成纤维细胞导致这些细胞类型的相互激活。然而，导致SSc MØ的因素 激活未知。在这方面，我们新的初步研究表明SSc真皮成纤维细胞来源的 外泌体作为介导SSc中MMP 3激活的介质。我们发现SSc真皮成纤维细胞来源的吸收 外泌体诱导促纤维化MMP 3活化。此外，SSc成纤维细胞激活的MSPs刺激SSc成纤维细胞， 产生炎性细胞因子和细胞外基质（ECM）成分。因此，我们假设 外泌体刺激的MCs和SSc成纤维细胞参与相互激活。本研究的目的 目的是确定分泌的成纤维细胞来源的外泌体和巨噬细胞促进纤维化的机制， 以及SSc中的炎症激活。我们将定义分子机制，途径和关键分子 介导SSc中成纤维细胞外泌体和MIBs之间的串扰，并将测试 使用最近开发的3D人类SSc皮肤模型靶向这些调节器。这项工作的结果将提供 为SSc开发新的有效治疗方法奠定了合理的基础。这些目标将在 该应用程序是： 1.定义成纤维细胞外泌体货物，并确定在SSc中调节MMP 3激活的组分。 基因组和分子生物学方法将用于鉴定诱导细胞凋亡的外泌体介质。 SSc Mc的激活，并确定这种激活的信号通路。 2.确定外泌体介导的MMP 3激活变化如何促进SSc的炎症和纤维化。 共培养研究表明，SSc MIBs诱导SSc成纤维细胞的活化，暗示了SSc MIBs的作用。 在纤维化的诱导和维持中的血管内皮衍生因子。这一目标将决定SSc如何管理 活化影响成纤维细胞活化。

ABSTRACT Systemic sclerosis (SSc) is a chronic autoimmune disease of unknown etiology that is characterized by vasculopathy, fibrosis, and inflammation. There is no cure for SSc and there are very few FDA-approved disease- modifying treatments. While the contribution of fibroblasts to disease development is widely appreciated, recent studies suggest macrophages (MØs) also play a role in the pathogenesis of SSc. In recently published work, we developed an immunophenotypic profile for SSc MØs, and demonstrated that co-culture of MØs with SSc dermal fibroblasts resulted in mutual activation of these cell types. However, the factors responsible for SSc MØ activation are unknown. In this regard, our new preliminary studies implicate SSc dermal fibroblast-derived exosomes as mediators of MØ activation in SSc. We show that uptake of SSc dermal fibroblast-derived exosomes induces profibrotic MØ activation. In addition, SSc fibroblast-activated MØs stimulate SSc fibroblast production of inflammatory cytokines and extracellular matrix (ECM) components. Therefore, we hypothesize that exosome-stimulated MØs and SSc fibroblasts engage in reciprocal activation. The goal of this study is to determine the mechanisms through which secreted fibroblast-derived exosomes and MØs promote fibrotic and inflammatory activation in SSc. We will define the molecular mechanisms, pathways, and key molecules that mediate cross-talk between fibroblast exosomes and MØs in SSc, and will test the therapeutic efficacy of targeting these regulators using a recently developed 3D human SSc skin model. Results of this work will provide the rational basis for the development of novel and effective treatments for SSc. The aims that will be tested in this application are: 1. Define fibroblast exosomal cargo and identify the components that regulate MØ activation in SSc. Genomic and molecular biology approaches will be used to identify the exosome mediators that induce SSc MØ activation and to identify the signaling pathways that underlie this activation. 2. Determine how exosomal-mediated changes in MØ activation promote inflammation and fibrosis in SSc. Co-culture studies demonstrate that SSc MØs induce activation of SSc fibroblasts, implicating a role for MØ-derived factors in the induction and maintenance of fibrosis. This aim will determine how SSc MØ activation impacts fibroblast activation.