Matrix-Myosin II Interactions Drive Fibrosis in Idiopathic Pulmonary Fibrosis.

摘要/研究总结 特发性肺纤维化（IPF）的特征在于进行性肺瘢痕形成和硬化，通过 “促纤维化”成纤维细胞。最近的研究表明，促纤维化行为，如增强的 迁移或肌成纤维细胞分化，可以由周围的肺基质驱动，但特异性 生物物理基质性质，这些信号转导的实际分子途径，或其 对体内纤维化的下游后果尚未完全阐明。虽然运动蛋白非- 已知肌肉肌球蛋白II（NMM 2）在产生细胞骨架张力中起作用， 成纤维细胞迁移和肌成纤维细胞分化在组织培养塑料上的传统实验室测定中， NMM 2在成纤维细胞对生物物理基质信号（如体内遇到的信号）的反应中的作用，或 NMM 2在IPF中促纤维化成纤维细胞表型中的作用尚不清楚。本研究计划调查 肺基质信号在IPF中驱动NMM 2介导的促纤维化成纤维细胞行为中的作用。长期 我们研究的目的是确定一种治疗策略，以阻止IPF的纤维化。我们的初步数据显示 1）正常肺的线性基质纤维组织协调NMM 2的外周激活， 2）纤维化肺的硬度激活NMM 2集中在成纤维细胞，以增强极化迁移， 成纤维细胞促进肌成纤维细胞分化，和3）IPF成纤维细胞中过度的NMM 2活化导致 促纤维化表型。因此，我们提出了一个新的假设：NMM 2是一个关键的驱动程序， 成纤维细胞表型通过其响应生物物理基质信号。这一假设将通过 三个相互关联但独立的具体目标：1）确定NMM 2 活化驱动成纤维细胞迁移和肌成纤维细胞分化; 2）确定细胞内 NMM 2可以介导迁移和肌成纤维细胞分化的机制， 生物物理基质线索;和3）确定NMM 2在小鼠体内肺纤维化中的作用。我们 该提案在概念上具有创新性，因为它首次将NMM 2作为IPF纤维化的关键驱动因素。的 拟议的研究是重要的，因为它可能发现一种新的治疗方法，以阻止疾病进展， IPF和其他纤维化疾病。这项研究将在克利夫兰的奥尔曼博士的实验室进行。 临床勒纳研究所（LRI），并将由国际领导人在纤维化领域的建议， 肌球蛋白生物学和生物机械工程。沿着我的导师，顾问团已经创建了一个 结构化的职业发展计划，包括细胞生物学和转化研究的正式课程。 一个理想的智力和协作环境是在LRI的地方。我的职业目标是建立和领导一个 独立研究项目，将促进IPF领域的科学知识和患者护理。我 对研究的承诺，强有力的指导，以及我的机构致力于培养下一代 科学研究者，将允许我建立一个成功的职业生涯作为一个物理学家科学家。

ABSTRACT / RESEARCH SUMMARY Idiopathic pulmonary fibrosis (IPF) is characterized by progressive lung scarring and stiffening, propagated by “pro-fibrotic” fibroblasts. Recent studies have demonstrated that pro-fibrotic behavior, such as enhanced migration or myofibroblast differentiation, can be driven by the surrounding lung matrix, but the specific biophysical matrix properties, the actual molecular pathway by which these signals are transduced, or its downstream consequences on in vivo fibrosis, have not been fully elucidated. Although the motor protein non- muscle myosin II (NMM2) is known to play a role in generating the cytoskeletal tension required for both fibroblast migration and myofibroblast differentiation in traditional laboratory assays on tissue culture plastic, the role of NMM2 in fibroblast responses to biophysical matrix signals like those encountered in vivo, or NMM2’s role in the pro-fibrotic fibroblast phenotype in IPF, are not known. This research proposal investigates the role of lung matrix signals in driving NMM2-mediated pro-fibrotic fibroblast behavior in IPF. The long-term goal of our studies is to identify a therapeutic strategy to halt fibrogenesis in IPF. Our preliminary data show that 1) the linear matrix fiber organization of normal lung coordinates peripheral activation of NMM2 in fibroblasts to enhance polarized migration, 2) the stiffness of fibrotic lung activates NMM2 centrally in fibroblasts to promote myofibroblast differentiation, and 3) excessive NMM2 activation in IPF fibroblasts leads to a pro-fibrotic phenotype. Therefore, we proposed the novel hypothesis: NMM2 is a key driver of the fibroblast phenotype through its response to biophysical matrix signals. This hypothesis will be tested through three interrelated, but independent specific aims: 1) to determine the biophysical matrix signal by which NMM2 activation drives fibroblast migration and myofibroblast differentiation; 2) to determine the intracellular mechanism by which NMM2 can mediate both migration and myofibroblast differentiation in response to biophysical matrix cues; and 3) to determine the role of NMM2 in pulmonary fibrogenesis in vivo in mice. Our proposal is innovative in concept, as it is the first to implicate NMM2 as a key driver of fibrosis in IPF. The proposed research is significant as it may discover a novel therapeutic approach to halt disease progression in IPF and other fibrotic disorders. The research will be carried out in the laboratory of Dr. Olman at the Cleveland Clinic Lerner Research Institute (LRI), and will be advised by international leaders in the fields of fibrosis, myosin biology, and biomechanical engineering. Along with my mentor, the advisory panel has created a structured career development program, including formal coursework in cell biology and translational research. An ideal intellectual and collaborative environment is in place at the LRI. My career goal is to build and lead an independent research program that would advance scientific knowledge and patient care in the field of IPF. My commitment to research, strong mentorship, and the dedication of my institution to training the next generation of scientific investigators, will allow me to build a successful career as a physician-scientist.