Genetic Susceptibility to Nanoparticle-Induced Respiratory Disease

描述（由申请人提供）：纳米技术的快速发展将伴随着数百万人接触到含有纳米材料的产品。碳纳米管（CNTs）是一种主要的工程纳米材料，在原子水平上设计和修饰，用于多种用途（电子，工程，医学）。虽然碳纳米管有许多有益的用途，但也有强有力的证据表明，它们会导致小鼠和大鼠的肺损伤和呼吸道疾病。一个主要问题是碳纳米管具有与石棉类似的特性，石棉是一种与肺纤维化（组织瘢痕）和间皮瘤（肺胸膜表面的一种罕见癌症）的发生有关的纤维。我们发现小鼠吸入的碳纳米管迁移到胸膜（肺周围敏感的间皮层），导致胸膜损伤和炎症。我们还报道了CNTs增加预先暴露于过敏原或细菌脂多糖的小鼠的肺纤维化。在人类广泛接触碳纳米管之前，了解碳纳米管如何在小鼠中引起呼吸系统疾病，特别是纤维化和癌症，并确定易感因素以明确评估风险是至关重要的。本提案的总体目标是阐明碳纳米管毒性使用基因工程小鼠模型对特定呼吸道疾病的易感性；特别是肺纤维化和间皮瘤。我们进一步试图确定通过原子层沉积（ALD）获得的选择性表面涂层（一种工程纳米级结构的新技术）是否影响碳纳米管减轻或加剧这些呼吸系统疾病的潜力。本提案中需要验证的具体假设是，cnt诱导的肺纤维化和间皮瘤的易感性是由于COX-2、STAT-1和p53之间的表达减少或功能相互作用受损。将进行以下具体目的来验证这一假设：在Aim 1中，我们将确定暴露于ALD-CNTs后COX-2是否介导p53水平升高，以及COX-2缺失是否会降低暴露小鼠肺部的p53水平，从而导致纤维化或间皮瘤。在Aim 2中，我们将确定暴露于ALD-CNTs后STAT-1激活是否诱导和激活p53，以及STAT-1缺失是否会减少暴露小鼠肺部的p53，从而导致纤维化或间皮瘤。在Aim 3中，我们将确定暴露于CNTs后p53缺陷小鼠是否容易发生肺纤维化或发生间皮瘤，以及ALD修饰CNTs是否会改变疾病结局。在Aim 4中，我们将确定ald修饰的CNTs是否通过ROS作为近端信号激活MAPKs以诱导COX-2、STAT-1或p53，以及COX-2、STAT-1或p53的缺失是否会放大CNTs诱导的MAPK信号。这种新方法将为碳纳米管引起呼吸系统疾病的机制提供有价值的信息。此外，我们将确定特定的基因，其缺陷将使个体面临更大的风险，导致碳纳米管暴露。我们的方法还利用了一种创新的跨学科方法，专门修改碳纳米管的表面化学，以确定毒性和疾病易感性是否增加或减少。对CNTs促进小鼠慢性肺部疾病的分子机制的新见解将提高我们对特定类型肺部疾病易感性的理解。

DESCRIPTION (provided by applicant): Rapid advances in nanotechnology will be accompanied by the exposure of millions of individuals to products containing nanomaterials. Carbon Nanotubes (CNTs) are a major type of engineered nanomaterial designed and modified at the atomic level for multiple uses (electronics, engineering, medicine). While there are many beneficial uses for CNTs, there is also strong evidence that they cause lung injury and respiratory disease in mice and rats. A major concern is that CNTs have some properties similar to asbestos, a fiber that is linked with the development of pulmonary fibrosis (tissue scarring) and mesothelioma (a rare cancer on the pleural surface of the lung). We discovered that inhaled CNTs migrate to the pleura (the sensitive mesothelial lining surrounding the lungs) in mice to cause pleural injury and inflammation. We have also reported that CNTs increase pulmonary fibrosis in mice pre-exposed to allergens or bacterial lipopolysaccharide. It is paramount to understand how CNTs cause respiratory diseases in mice, especially fibrosis and cancer, before human exposures become widespread and identify susceptibility factors to clearly evaluate risk. The overall goal of this proposal is to elucidate CNT toxicity using genetically engineered mouse models of susceptibility to specific respiratory diseases; specifically pulmonary fibrosis, and mesothelioma. We further seek to determine whether selective surface coatings achieved by atomic layer deposition (ALD), a novel technique of engineering nanoscale structures, affect the potential of CNTs to mitigate or exacerbate these respiratory diseases. The specific hypothesis to be tested in this proposal is that susceptibility to CNT-induced pulmonary fibrosis and mesothelioma is due to reduced expression or impaired functional interaction between COX-2, STAT-1, and p53. The following specific aims will be carried out to test this hypothesis: In Aim 1, we will determine whether COX-2 mediates increased p53 levels after exposure to ALD-CNTs and whether COX-2 deletion reduces p53 levels in the lungs of exposed mice to cause fibrosis or mesothelioma. In Aim 2, we will determine whether STAT-1 activation induces and activates p53 after exposure to ALD-CNTs and whether STAT-1 deletion reduces p53 in the lungs of exposed mice to cause fibrosis or mesothelioma. In Aim 3, we will determine whether p53-deficient mice are susceptible to pulmonary fibrosis or develop mesothelioma after exposure to CNTs and whether ALD modification of CNTs alters disease outcome. In Aim 4, we will determine whether ALD-modified CNTs activate MAPKs via ROS as a proximal signal to induce COX-2, STAT-1, or p53, and whether loss of COX-2, STAT-1, or p53 amplifies CNT-induced MAPK signaling. This novel approach will provide valuable information on mechanisms through which CNTs cause respiratory diseases. Moreover, we will identify specific genes whose deficiency will put individuals at greater risk resulting from CNT exposure. Our approach also takes advantage of an innovative cross-disciplinary approach to specifically modify the surface chemistry of carbon nanotubes to determine whether toxicity and disease susceptibility are increased or decreased. The new insights into the molecular mechanisms through which CNTs promote chronic lung disease in mice will improve our understanding of susceptibility to specific types of lung disease. The broad impact of this work will directly affect the health and well-being of millions of individuals in the U.S. and worldwide by providing essential information for the design of safer nanomaterials.