Nanoparticle properties and alveolar epithelial barrier/transport functions

项目总结 吸入超细(纳米)颗粒与心血管、肺和 血液学效应，血管和终末器官中颗粒的定位，以及增加发病率和 易感人群死亡率。由于颗粒物是被吸入的，它们最有可能进入 全身循环穿过肺泡上皮。尽管纳米颗粒的利用是由于 预计纳米技术的科学和应用范围的扩大将显著增加， 纳米颗粒损伤和/或转运进入/穿过肺泡上皮的机制尚不清楚 为人所知。基于我们对几类纳米颗粒的肺损伤/摄取/转运的初步数据 (由聚苯乙烯、二氧化硅和金属(氧化物)组成)，具有明确的物理化学特征和最近 关于吸入超细空气污染物颗粒物对健康影响的报告，我们假设 纳米粒和肺泡上皮细胞I)可以破坏正常肺泡上皮细胞的动态平衡，并诱导 细胞特性和肺泡上皮屏障功能的变化，II)提供了进入肺组织的主要通道 通过跨皮细胞转位途径进入体循环的纳米颗粒，以及iii)高度 取决于纳米颗粒的物理化学性质。利用定义的聚苯乙烯、二氧化硅和金属 (氧化物)纳米颗粒在体外模型中(包括我们建立的大鼠原代培养单层或 人肺泡上皮细胞)和大鼠肺，我们将通过研究 主要目的如下：1)纳米颗粒对肺泡主动和被动屏障性能的影响 2)纳米粒在肺泡上皮细胞中的内化、去向和作用；3)转运 纳米粒子在体外穿过肺泡上皮；4)纳米粒子在大鼠肺部的内化和转运 在体内，与体内和体外的远端呼吸道上皮损伤/摄取/运输相关。在……里面 此外，我们将利用在渗透性过滤器和巨型过滤器上重建的人工脂双层的简化模型 单层囊泡，确定被动机制(例如，扩散)和/或破坏脂质的作用(S) 纳米颗粒中的双层进入/退出肺泡上皮细胞。建议的调查结果 本文将提供对纳米颗粒的细胞毒性和内化/转运机制的见解。 明确的进入/穿过肺泡上皮的物理化学特性。我们的主要目标是获得 纳米颗粒与肺泡上皮相互作用的新信息，以帮助了解对肺泡上皮细胞的影响 吸入人工纳米颗粒和环境空气污染物超细颗粒物的肺，点 管理由此产生的有害影响的指导方针，并导致定义的改进设计 用于更安全和更有效的生物医学应用的纳米颗粒(例如，肺部药物/基因输送)。

PROJECT SUMMARY Inhalation of ultrafine (nano)particles has been associated with adverse cardiovascular, pulmonary and hematologic effects, localization of particles in blood vessels and end organs, and increased morbidity and mortality in susceptible populations. Since the particles are inhaled, their most likely route of entry into the systemic circulation is across the alveolar epithelium of the lung. Although utilization of nanoparticles due to expansion of the science and application of nanotechnology is expected to markedly increase, the mechanisms by which nanoparticles injure and/or are transported into/across alveolar epithelium are not well known. Based on our preliminary data on lung injury/uptake/trafficking of several classes of nanoparticles (composed of polystyrene, silica and metal (oxides)) with defined physicochemical characteristics and recent reports on health effects of inhaled ultrafine air pollutant particulates, we hypothesize that interactions between nanoparticles and alveolar epithelial cells i) can disrupt normal alveolar epithelial cell homeostasis and induce changes in cellular properties and alveolar epithelial barrier function, ii) provide the primary portal of entry for nanoparticles into the systemic circulation via transepithelial translocation pathways, and iii) are highly dependent on physicochemical properties of the nanoparticles. Utilizing defined polystyrene, silica and metal (oxide) nanoparticles in in vitro models (including our well-established primary cultured monolayers of rat or human alveolar epithelial cells) and rat lungs in vivo, we will test these hypotheses by investigating the following four major aims: 1) nanoparticle effects on active and passive barrier properties of alveolar epithelium; 2) internalization, fate and effects of nanoparticles in alveolar epithelial cells; 3) trafficking of nanoparticles across alveolar epithelium in vitro; and 4) nanoparticle internalization and trafficking in rat lungs in vivo, correlating injury to/uptake into/trafficking across distal respiratory epithelium in vivo vs in vitro. In addition, we will utilize simplified models of artificial lipid bilayers reconstituted on permeable filters and giant unilamellar vesicles to determine the role(s) of passive mechanisms (e.g., diffusion) and/or disruption of lipid bilayers in nanoparticle entry into/exit from alveolar epithelial cells. Findings from the investigations proposed herein will provide insights into cytotoxicity and mechanisms of internalization/trafficking of nanoparticles with defined physicochemical properties into/across the lung alveolar epithelium. Our major objective is to obtain new information on nanoparticle interactions with alveolar epithelium in order to help understand effects on the lung of inhaled manufactured nanoparticles and environmental air pollutant ultrafine particulates, point directions for management of resultant deleterious effects, and lead to improved design of defined nanoparticles for safer and more efficient biomedical applications (e.g., pulmonary drug/gene delivery).