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

摘要/研究总结 特发性肺纤维化(IPF)的特征是进行性肺疤痕形成和僵硬，由 “促纤维化”的成纤维细胞。最近的研究表明，促肝纤维化的行为，如增强 迁移或肌成纤维细胞分化，可由周围肺基质驱动，但特异性 生物物理基质属性，这些信号被转导的实际分子路径，或其 体内纤维化的下游后果还没有完全阐明。尽管马达蛋白不是 众所周知，肌肉肌球蛋白II(NMM2)在两者所需的细胞骨架张力的产生中发挥作用 组织培养塑料上成纤维细胞迁移和肌成纤维细胞分化的传统实验室检测， NMM2在成纤维细胞对生物物理基质信号的反应中的作用 NMM2的S在IPF中促纤维化成纤维细胞表型中的作用尚不清楚。这项研究建议调查 肺基质信号在IPF中NMM2介导的促纤维化成纤维细胞行为中的作用。长期的 我们研究的目标是确定一种阻止IPF纤维化形成的治疗策略。我们的初步数据显示 1)正常肺线性基质纤维组织协调NMM2的外周激活 成纤维细胞促进极化迁移，2)纤维化肺的僵硬集中激活NMM2。 成纤维细胞促进肌成纤维细胞分化；3)IPF成纤维细胞中NMM2过度激活导致 转化为支持纤维化的表型。因此，我们提出了新的假设：NMM2是一个关键的驱动因素 成纤维细胞的表型通过其对生物物理基质信号的反应来实现。这一假设将通过 三个相互关联但独立的具体目标：1)确定NMM2通过 激活驱动成纤维细胞迁移和肌成纤维细胞分化；2)确定细胞内 NMM2介导细胞迁移和肌成纤维细胞分化的机制 生物物理基质提示；以及3)确定NMM2在小鼠体内肺纤维化中的作用。我们的 该提案在概念上是创新的，因为它是第一个将NMM2作为IPF纤维化的关键驱动因素的方案。这个 拟议的研究具有重要意义，因为它可能会发现一种新的治疗方法，以阻止疾病的进展 IPF和其他纤维性疾病。这项研究将在克利夫兰大学奥尔曼博士的实验室进行。 临床勒纳研究所(LRI)，并将由纤维化领域的国际领导人提供建议， 肌球蛋白生物学和生物力学工程。与我的导师一起，顾问小组创建了一个 有组织的职业发展计划，包括细胞生物学和翻译研究的正式课程。 LRI拥有理想的智力和协作环境。我的职业目标是建立和领导一个 独立研究计划，将促进IPF领域的科学知识和患者护理。我的 致力于研究，强大的导师，以及我的机构致力于培训下一代 科学研究人员，将使我能够建立一个成功的职业生涯，作为一名内科科学家。

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.