THE ROLE OF PULMONARY SUBPOPULATIONS AND TH2 IMMUNITY IN BALB/C SILICOSIS MODEL

肺亚群和 TH2 免疫在 BALB/C 硅肺模型中的作用

• 批准号: 8360469
• 负责人: CHRISTOPHER Todd MIGLIACCIO
• 金额: $ 2.05万
• 依托单位: UNIVERSITY OF MONTANA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8360469
• 关键词: Alveolar Macrophages; Bone Marrow; Cessation of life; Chronic; Development; Disease; Environment; Environmental Health; Evaluation; Event; Exposure to; Fibrosis; Flow Cytometry; Funding; Grant; Immune; Immunity; Immunosuppressive Agents; In Vitro; Inbred BALB C Mice; Inflammatory; Insulin-Like Growth Factor I; Interleukin Activation; Interleukin-4; Interleukins; Laboratories; Lung; Lung Inflammation; Messenger RNA; Modeling; Mus; National Center for Research Resources; Occupational; Particulate; Pathway interactions; Principal Investigator; Process; Production; Property; Pulmonary Fibrosis; Research; Research Infrastructure; Resources; Role; Silicon Dioxide; Silicosis; Source; Staging; System; Testing; United States National Institutes of Health; base; cell type; cost; cytotoxic; human disease; interstitial cell; macrophage; mouse model; particle; respiratory

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Specific Aims and Hypothesis Prolonged exposure to crystalline silica in occupational and environmental settings induces chronic lung inflammation that can progress to fibrosis, i.e. silicosis. The interaction of pulmonary macrophages with silica is considered a key event in the disease process (1, 2). Furthermore, the environment of the lung is considered immunosuppressive; therefore, the induction of a chronic inflammatory condition like silicosis is the result of a disruption of the typical immunomodulatory environment of the lung. While a portion of this disruption is most likely due to the cytotoxic properties of silica particles, not all pulmonary macrophages die following interaction with the particulates. In fact we have documented increased activation of some macrophages in the mouse model. Respiratory exposure of mice (either Balb/c or C57Bl/6 common wild type strains) to crystalline silica results in pulmonary fibrosis, and has proven an effective model of the human disease. The Balb/c silicosis model has been shown, by our laboratory and others, to require Th2 immunity for progression to fibrosis (3-5). To date our laboratory has found several components associated with Th2 immunity to be significantly increased following exposure to crystalline silica including markers of alternatively activated macrophages (aaMac), interleukin (IL)-4+ interstitial cells, and insulin-like growth factor (IGF)-1. In addition, we have found a subset of pulmonary macrophages that express Akt, a key component of the survival pathway instigated by IGF-1, and appear to be predisposed to survival in the early stages of the disease. We propose to test the central hypothesis that multiple cells types and soluble factors that are associated with Th2 immunity are significantly increased in the Balb/c model of silicosis and that they all contribute to altered immune-activated environment of the disease. We will use the following two aims to test this hypothesis (as depicted in Fig. 1 schematic): Specific Aim 1: Evaluation of inflammasome activation in macrophage subsets of the lung following exposure to crystalline silica. Hypothesis: A subset of pulmonary macrophages induces the inflammasome pathway associated with IL-33 production and promotes a pro-fibrotic environment in the silicosis model. Using a combination of flow cytometry and mRNA analysis, pulmonary macrophage subsets will be defined based on inflammasome activation and IL-33 production. Specific Aim 2: Define the interaction of the inflammasome and survival (IGF-1-Akt) pathways following exposure to crystalline silica. Hypothesis: Silica induces both death and survival in particular macrophage subsets, both of which act synergistically to contribute to the pro-fibrotic environment of the silicosis model. Using in vitro culture systems (primary AM and bone marrow-derived macrophages) both the inflammasome and survival pathways will be activated with various stimulants in the presence of crystalline silica particles to assess their interaction in the development of a pro-fibrotic environment.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的主要研究者可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 具体目标和假设 在职业和环境中长期接触结晶二氧化硅会诱发慢性肺部炎症，进而发展为纤维化，即硅肺。肺巨噬细胞与二氧化硅的相互作用被认为是疾病过程中的关键事件 (1, 2)。 此外，肺部环境被认为是免疫抑制的；因此，像矽肺这样的慢性炎症的诱发是肺部典型免疫调节环境破坏的结果。 虽然这种破坏的部分原因很可能是由于二氧化硅颗粒的细胞毒性特性，但并非所有肺巨噬细胞在与颗粒相互作用后都会死亡。 事实上，我们已经记录了小鼠模型中一些巨噬细胞的激活增加。 小鼠（Balb/c 或 C57Bl/6 常见野生型菌株）呼吸暴露于结晶二氧化硅会导致肺纤维化，并已被证明是人类疾病的有效模型。我们的实验室和其他实验室已证明 Balb/c 硅肺模型需要 Th2 免疫才能进展为纤维化 (3-5)。迄今为止，我们的实验室发现，接触结晶二氧化硅后，与 Th2 免疫相关的多种成分显着增加，包括替代激活巨噬细胞 (aaMac)、白细胞介素 (IL)-4+ 间质细胞和胰岛素样生长因子 (IGF) 的标记物-1。此外，我们还发现了表达 Akt 的肺巨噬细胞子集，Akt 是 IGF-1 引发的生存途径的关键组成部分，并且似乎在疾病的早期阶段易于生存。 我们建议检验一个中心假设，即与 Th2 免疫相关的多种细胞类型和可溶性因子在矽肺 Balb/c 模型中显着增加，并且它们都有助于改变该疾病的免疫激活环境。 我们将使用以下两个目标来检验这个假设（如图1示意图所示）： 具体目标 1：评估暴露于结晶二氧化硅后肺部巨噬细胞亚群中炎症小体的激活。 假设：肺巨噬细胞的一个子集诱导与 IL-33 产生相关的炎症小体途径，并促进矽肺模型中的促纤维化环境。 结合流式细胞术和 mRNA 分析，将根据炎性体激活和 IL-33 产生来定义肺巨噬细胞亚群。 具体目标 2：定义暴露于结晶二氧化硅后炎症小体和存活 (IGF-1-Akt) 途径的相互作用。 假设：二氧化硅诱导特定巨噬细胞亚群的死亡和存活，两者协同作用，有助于矽肺模型的促纤维化环境。 使用体外培养系统（原代 AM 和骨髓来源的巨噬细胞），在存在结晶二氧化硅颗粒的情况下，将用各种兴奋剂激活炎症小体和生存途径，以评估它们在促纤维化环境发展中的相互作用。