Study on effects and transport of nanoparticles through alveolar wall

我们利用肺泡上皮细胞和内皮细胞制备了一个体外肺泡毛细血管屏障模型，以评估纳米颗粒在呼吸系统中的行为。胶体金或荧光标记的聚苯乙烯颗粒（200 nm和20 nm）被肺泡上皮细胞通过吞噬或内吞作用吸收。100 nm颗粒仅存在于肺泡上皮细胞中，20 nm颗粒存在于内皮细胞中，提示20 nm颗粒而不是200nm颗粒具有穿透肺泡-毛细血管屏障模型的能力。多壁、单壁碳纳米管和200nm聚苯乙烯颗粒诱导肺泡上皮细胞血红素加氧酶-1，而20nm颗粒对肺泡上皮细胞无诱导作用。未观察到细胞因子（IL-1β和TNF-α）的分泌和NF-κB的活化。在暴露于碳纳米管的细胞中观察到MAP激酶的活化。为了研究纳米颗粒沉积在呼吸道中的行为，我们还完成了一项使用胶体金颗粒和荧光标记聚苯乙烯颗粒（20 nm, 200nm, FluoSphere）的气管内滴注研究。羧化修饰微球，红色荧光580/605)。大多数颗粒见于肺泡巨噬细胞。值得注意的是，20nm颗粒存在于微血管中，而聚集的20nm和200nm颗粒已被肺泡巨噬细胞和肺泡上皮细胞吞噬。心腔、肝、肾血管均可见含颗粒的肺泡巨噬细胞。ICP-MS分析显示，注射2小时后，血液、心脏、肝脏、肾脏、脾脏、淋巴结中均检出少量金。为了研究纳米颗粒沉积在呼吸道中的影响，我们还完成了使用单壁和多壁碳纳米管、富勒烯、氧化钛的气管内滴注研究。单壁碳纳米管和多壁碳纳米管（10 μg/只、50μg/只）均可检测到细胞因子（IL-1β、TNF-α、TGF-β）分泌的上调。碳纳米管的灌注引起肺部炎症、肉芽肿和弱纤维化。这些结果表明，20nm的纳米颗粒可能穿透肺泡壁（上皮细胞、基底膜和内皮细胞），并有可能直接迁移到循环中，尽管这需要使用电子显微镜进行额外的研究来证实“直接迁移”的情况。少

We have prepared an in vitro alveolo-capillary barrier model using alveolar epithelial and endothelial cells to evaluate the behavior of nanoparticles in the respiratory system. Colloidal gold or fluorescent-tagged polystyrene particles of 200 nm and 20 nm were taken up by the alveolar epithelial cells by phagocytosis or endocytosis. Twe hundred nm particles were present only in the alveolar epithelial cells and 20 nm particles were found in the endothelial cells, suggesting that 20 nm but not 200nm particles have an ability to penetrate the alveolo-capillary barrier model. Multi-wall and single-wall carbon nanotubes and 200nm polystyrene particles induced hemeoxygenase-1 in alveolar epithelial cells but 20 nm particles did not. Secretion of cytokines (IL-1β and TNF-α) or activation of NF-κB were not observed. Activation of MAP kinase was observed in cells exposed to carbon nanotubes.To investigate the behavior of nanoparticles deposited in the respiratory airways, we have also complet … More ed an intratracheal instillation study using colloidal gold particles and fluorescent-tagged polystyrene particles (20 nm, 200nm, FluoSphere【○!R】carboxylated-modifiedmicrospheres, red fluorescent 580/605). Most of the particles were found in alveolar macrophages. It is of interest to note that the 20nm particles were present in the microvessel, while the aggregated 20nm and 200nm particles that had been engulfed by alveolar macrophages and alveolar epithelial cells. Alveolar macrophages containing particles were observed in the cavity of heart, the vessel of liver and kidney. ICP-MS analysis revealed that a little amount of gold was detected in blood, heart, liver, kidney, spleen, lymph node after 2 hr instillation.To investigate the effect of nanoparticles deposited in the respiratory airways, we have also completed an intratracheal instillation study using single and maulti-wall carbon nanotubes, fullerene, titanium oxide. Activation of NF-κB were not observed, but upregulation of cytokine secretion (IL-1β, TNF-α, and TGF-β) was detected by instillation of single and multi-wall carbon nanotubes (10 and 50μg/mouse). Instillation of carbon nanotubes induced inflammation, granulomas, and weak fibrosis in lung.These results suggest that nanoparticle of 20 nm may penetrate the alveolar wall (epithelial cells, basement membrane, and endothelial cells) and has a potency to migrate directly into the circulation, although it requires an additional study using electron microscopy to confirm the "Direct migration" scenario. Less