Targeting HSC-derived Circulating Fibroblast Precursors in Pulmonary Fibrosis

靶向 HSC 衍生的循环成纤维细胞前体治疗肺纤维化

• 批准号: 8966667
• 负责人: AMANDA C. LARUE
• 金额: --
• 依托单位: RALPH H JOHNSON VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-10-01 至 2017-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8966667
• 关键词: Age; Alveolar; Architecture; Autologous; Automobile Driving; Biological Markers; Blood Circulation; Bone Marrow; Breathing; Cell Transplantation; Cells; Chronic; Chronic lung disease; Clonal Hematopoietic Stem Cell; DDR2 gene; Data; Development; Diagnosis; Disease; Disease Progression; Dust; Effector Cell; Environmental Hazards; Epithelial Cell Proliferation; Evaluation; Exposure to; Extracellular Matrix; FDA approved; Fibroblasts; Fibrosis; Figs - dietary; Flow Cytometry; Gases; Goals; Gulf War; Health; Hematopoietic stem cells; Heterogeneity; Human; In Vitro; Incidence; Lead; Lung; Lung diseases; Methods; Mission; Modeling; Molecular; Mus; Myofibroblast; PTPRC gene; Particulate; Patients; Phenotype; Population; Population Heterogeneity; Pulmonary Fibrosis; Pulse Oximetry; Respiration Disorders; Risk; Role; Silicon Dioxide; Soldier; Staining method; Stains; Testing; Therapeutic; Tissues; Transplantation; Treatment Effectiveness; Veterans; Xenograft Model; alveolar type II cell; base; effective therapy; enhanced green fluorescent protein; environmental chemical; hazard; human disease; improved; in vitro testing; in vivo; insight; microCT; monocyte; new therapeutic target; novel; paracrine; particle; peripheral blood; persistent symptom; progenitor; reconstitution; response; therapeutic target; trafficking

DESCRIPTION (provided by applicant): Exposure to environmental and chemical hazards is thought to be a major contributing factor to Gulf War illness (GWI) (US Dept VA). Of particular concern for Gulf War Veterans is chronic inhalation of sand, dust and airborne particulates while in theater which pose significant risk for development of respiratory diseases including pulmonary fibrosis (PF). PF is a chronic lung disease characterized by accumulation of extracellular matrix (ECM), destruction of normal lung architecture, and decreased capacity for gas exchange. The activated fibroblast is the primary effector cell in PF. However, targeting activated fibroblasts is challenging due, in part, to the heterogeneity of the population. This heterogeneity is thought to reflect the multiple proposed origins of fibroblasts, making it essential to elucidate the role of fibroblasts from all origins i PF. Using mice whose bone marrow was reconstituted by a clonal population of cells derived from a single enhanced green fluorescent protein positive (EGFP+) hematopoietic stem cell (HSC), we have demonstrated an HSC origin for fibroblasts and activated fibroblasts in multiple tissues. We also identified a CD45+DDR2+ HSC-derived circulating fibroblast precursor (CFP) in peripheral blood of mice and humans that is related to the monocyte, gives rise to activated fibroblasts, produces pro-fibrotic factors, increases with disease, and can be therapeutically targeted. Using a silica model of PF that mimics particulate exposure in Veterans of the Gulf War, we have shown that CFPs increase in circulation with PF and traffic to the fibrotic lung. Together, our findings support the hypothesis that HSC-derived CFPs are critical to progression of PF and can be targeted to inhibit fibrotic progression. This will be tested using our novel clonal HSC cell transplantation method in conjunction with a silica instillation PF model in three Specific Aims. Aim 1 will temporally examine CFP contribution to silica-induced PF and potential of CFPs to serve as an early biomarker for disease and/or response to therapy (Aim 1). Studies in Aim 2 will elucidate mechanisms regulating participation, activation and pro-fibrotic effects of CFPs. Finally, we will examine the effect of therapeutically targeting this unique fibrotic progenitor using both mouse-to-mouse transplant and human-to-mouse xenograft models to demonstrate that inhibition of CFPs can reduce progression of silica-based fibrosis and is applicable to human disease (Aim 3). The proposed studies are paradigm shifting in that most studies focus on targeting the activated fibroblast or relatively mature fibrocyte in fibrosis, whie our data suggests that the more primitive CFP may provide a more effective therapeutic target. These studies are significant in that they are the first to conduct flow cytometric, immunohistochemical, molecular, and functional evaluation of HSC-derived CFPs and their contribution to PF. It is suggested that the number of Veterans diagnosed with Gulf War Illness, including respiratory diseases, is grossly underestimated. As GWI is better defined and the Veteran population serving in the Gulf ages, we expect to see an increased incidence of PF in the Veteran population. Studying early markers of PF is of great relevance to the VA mission as it will allow us to better detect early signs of PF in patients, potentially using CFPs as a biomarker, to dramatically improve effectiveness of treatment prior to loss of normal lung architecture and function. Therefore, these studies have the potential to directly impact Gulf War Veterans' health as well as have far-reaching application to Veterans with multiple types of fibrotic disease.

描述（由申请人提供）： 暴露于环境和化学危害被认为是导致海湾战争疾病 (GWI) 的一个主要因素（美国退伍军人部）。海湾战争退伍军人特别关心的是在战区长期吸入沙子、灰尘和空气中的颗粒物，这对他们造成重大风险 包括肺纤维化（PF）在内的呼吸系统疾病的发展。 PF 是一种慢性肺部疾病，其特征是细胞外基质 (ECM) 积聚、正常肺结构破坏和气体交换能力下降。活化的成纤维细胞是 PF 中的主要效应细胞。然而，靶向活化的成纤维细胞具有挑战性，部分原因是群体的异质性。这种异质性被认为反映了成纤维细胞的多种起源，因此有必要阐明所有来源的成纤维细胞在 PF 中的作用。 使用由单个增强型绿色荧光蛋白阳性 (EGFP+) 造血干细胞 (HSC) 衍生的细胞克隆群重建骨髓的小鼠，我们证明了多个组织中成纤维细胞和活化成纤维细胞的 HSC 起源。我们还在小鼠和人类的外周血中发现了 CD45+DDR2+ HSC 衍生的循环成纤维细胞前体 (CFP)，它与单核细胞相关，可产生活化的成纤维细胞，产生促纤维化因子，随疾病而增加，并且可用于治疗有针对性。使用模拟海湾战争退伍军人的颗粒物暴露的 PF 二氧化硅模型，我们发现 CFP 的循环随着 PF 的增加而增加，并增加到纤维化肺部的流量。总之，我们的研究结果支持这样的假设：HSC 衍生的 CFP 对于 PF 的进展至关重要，并且可以靶向抑制纤维化进展。这将使用我们的新型克隆 HSC 细胞移植方法结合二氧化硅滴注 PF 模型在三个特定目标中进行测试。目标 1 将暂时检查 CFP 对二氧化硅诱导的 PF 的贡献以及 CFP 作为疾病和/或治疗反应的早期生物标志物的潜力（目标 1）。目标 2 的研究将阐明调节参与、激活和促纤维化作用的机制 CFP。最后，我们将使用小鼠对小鼠移植和人对小鼠异种移植模型来检查针对这种独特的纤维化祖细胞的治疗效果，以证明抑制 CFP 可以减少硅基纤维化的进展，并且适用于人类疾病（目标 3）。 拟议的研究是范式转变，因为大多数研究重点针对纤维化中活化的成纤维细胞或相对成熟的纤维细胞，而我们的数据表明更原始的 CFP 可能提供更有效的治疗靶点。这些研究意义重大，因为它们是第一个对 HSC 衍生的 CFP 及其对 PF 的贡献进行流式细胞术、免疫组织化学、分子和功能评估的研究。有人认为，被诊断患有海湾战争疾病（包括呼吸道疾病）的退伍军人人数被严重低估。随着 GWI 的定义更加明确以及在海湾地区服役的退伍军人群体的年龄增长，我们预计退伍军人群体中 PF 的发病率将会增加。研究 PF 的早期标志物与 VA 使命密切相关，因为它将使我们能够更好地检测患者 PF 的早期症状，并可能使用 CFP 作为生物标志物，在正常肺结构和功能丧失之前显着提高治疗效果。因此，这些研究有可能直接影响海湾战争退伍军人的健康，并对患有多种纤维化疾病的退伍军人具有深远的应用。