Fibrotic remodeling of lymph nodes disrupts T cell function in fibrosis and cancer

项目总结/摘要 纤维化是癌症的一个标志，其通过改变肿瘤细胞的免疫原性来促进增殖、转移和免疫逃避。 肿瘤间质占肿瘤质量的90%。在纤维化中，病原体偏离稳态 导致肌成纤维细胞过度沉积细胞外基质（ECM），产生离散区域， 无法修复的伤口纤维化ECM的这些区域成为细胞表型的主要调节因子， 提供生物化学（即ECM组合物和可溶性因子）和生物物理（即机械力 和材料性质）提示促进肿瘤进展和限制免疫细胞浸润。可溶性因子 在这些纤维化器官的间质空间内的淋巴液流入周围的淋巴结（LN）并诱导纤维化 LN中的重塑，这是癌症和其他纤维化病理中预后不良的常见标志。LN有一个 一种独特的微环境，称为管道系统，它运输抗原，并作为迁移 淋巴细胞的支架。在健康中，其组织促进T细胞和抗原呈递之间的相互作用 细胞，以确保强大的免疫激活，以应对癌症，病原体和损伤。成纤维网状细胞 （FRC）构建并包裹这种胶原网络，并产生促进T细胞存活的细胞因子， 体内平衡这种ECM网络的破坏导致T细胞失调和耗竭，涉及淋巴结转移。 纤维化在疾病进展中的作用LN纤维化的发生机制及LN纤维化对T细胞的影响 细胞功能知之甚少，但代表了一个有吸引力的治疗机会。在其他组织中， 重塑机械地硬化微环境，启动整联蛋白介导的信号级联。我 假设类似机制通过FRC驱动LN纤维化，并试图探索LN的重塑如何 微环境影响纤维化和癌症中T细胞应答的发展。 该提案的第一个目的（F99期）评估整合素信号传导是否通过促进LN纤维化来驱动LN纤维化。 FRC向肌成纤维细胞分化。这将部分通过分析来自特发性 肺纤维化和黑色素瘤患者与先进的机械生物学（原子力显微镜）和 空间组学成像（CODEX）方法来测量硬度、ECM含量和FRC/T细胞表型。的 在目标1中学到的知识和技能然后应用于目标2（K 00阶段），以研究纤维化对 肿瘤引流LN对黑色素瘤鼠模型中抗肿瘤T细胞应答的影响。

Project Summary/Abstract Fibrosis is a hallmark of cancer that promotes proliferation, metastasis, and immune evasion by altering the tumor stroma which accounts for up to 90% of tumor mass. In fibrosis, pathogenic departure from homeostasis results in the excessive deposition of extracellular matrix (ECM) by myofibroblasts, creating discrete regions of non-resolving wound repair. These regions of fibrotic ECM become dominant regulators of cell phenotype, providing both biochemical (i.e. ECM composition and soluble factors) and biophysical (i.e. mechanical forces and material properties) cues to promote tumor progression and restrict immune cell infiltration. Soluble factors within the interstitial space of these fibrotic organs drain into surrounding lymph nodes (LNs) and induce fibrotic remodeling in the LN, a common sign of poor prognosis in cancer and other fibrotic pathologies. LNs have a distinct microenvironment known as the conduit system, which traffics antigens and serves as a migratory scaffold for lymphocytes. In health, its organization facilitates interactions between T cells and antigen presenting cells to ensure robust immune activation in response to cancer, pathogens, and injury. Fibroblastic reticular cells (FRCs) construct and ensheath this collagenous network and produce cytokines that promote T cell survival and homeostasis. Disruption of this ECM network leads to T cell dysregulation and depletion, implicating lymph node fibrosis in disease progression. The mechanisms of fibrotic initiation in the LN and the effect of LN fibrosis in T cell function is poorly understood, yet represent an attractive therapeutic opportunity. In other tissues, fibrotic remodeling mechanically stiffens the microenvironment, initiating integrin-mediated signaling cascades. I hypothesize that similar mechanisms drive LN fibrosis by FRCs, and seek to explore how remodeling of the LN microenvironment affects development of T cell responses in fibrosis and cancer. The first aim of this proposal (F99 phase) evaluates whether integrin signaling drives LN fibrosis by promoting FRC-to-myofibroblast differentiation. This will be accomplished in part by analyzing LNs from Idiopathic Pulmonary Fibrosis and melanoma patients with advanced mechanobiological (atomic force microscopy) and spatial-omic imaging (CODEX) methods to measure stiffness, ECM content, and FRC/T cell phenotypes. The knowledge and skills learned in Aim 1 are then applied in Aim 2 (K00 phase) to study the impact of fibrosis in tumor draining LNs on anti-tumor T cell responses in murine models of melanoma.