Engineered nanoparticles (NP) are being developed for inhaled drug delivery. This route is non-invasive and the major target; alveolar epithelium provides a large surface area for drug administration and absorption, without first pass metabolism. Understanding the interaction between NPs and target cells is crucial for safe and effective NP-based drug delivery. We explored the differential effect of neutral, cationic and anionic polystyrene latex NPs on the target cells of the human alveolus, using primary human alveolar macrophages (MAC) and primary human alveolar type 2 (AT2) epithelial cells and a unique human alveolar epithelial type I-like cell (TT1). We hypothesized that the bioreactivity of the NPs would relate to their surface chemistry, charge and size as well as the functional role of their interacting cells in vivo. Amine- (ANP) and carboxyl- surface modified (CNP) and unmodified (UNP) polystyrene NPs, 50 and 100 nm in diameter, were studied. Cells were exposed to 1–100 μg/ml (1.25-125 μg/cm2; 0 μg/ml control) NP for 4 and 24 h at 37 °C with or without the antioxidant, N-acetyl cysteine (NAC). Cells were assessed for cell viability, reactive oxygen species (ROS), oxidised glutathione (GSSG/GSH ratio), mitochondrial integrity, cell morphology and particle uptake (using electron microscopy and laser scanning confocal microscopy). ANP-induced cell death occurred in all cell types, inducing increased oxidative stress, mitochondrial disruption and release of cytochrome C, indicating apoptotic cell death. UNP and CNP exhibited little cytotoxicity or mitochondrial damage, although they induced ROS in AT2 and MACs. Addition of NAC reduced epithelial cell ROS, but not MAC ROS, for up to 4 h. TT1 and MAC cells internalised all NP formats, whereas only a small fraction of AT2 cells internalized ANP (not UNP or CNP). TT1 cells were the most resistant to the effects of UNP and CNP. ANP induced marked oxidative damage and cell death via apoptosis in all cell types, while UNP and CNP exhibited low cytotoxicity via oxidative stress. MAC and TT1 cell models show strong particle-internalization compared to the AT2 cell model, reflecting their cell function in vivo. The 50 nm NPs induced a higher bioreactivity in epithelial cells, whereas the 100 nm NPs show a stronger effect on phagocytic cells.

中文翻译：

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中性，阳离子和阴离子聚苯乙烯纳米粒子与人肺泡腔室细胞的差异生物反应性：1型肺泡上皮细胞的强大反应。

工程纳米颗粒（NP）正在开发中，用于吸入药物输送。这条路线是非侵入性的，并且是主要目标。肺泡上皮为药物的给药和吸收提供了较大的表面积，而无需首过代谢。了解NP与靶细胞之间的相互作用对于安全有效地基于NP的药物递送至关重要。我们使用人类初级肺泡巨噬细胞（MAC）和人类初级肺泡2型（AT2）上皮细胞和独特的人类I型肺泡上皮细胞探索中性，阳离子和阴离子聚苯乙烯乳胶NPs对人类肺泡靶细胞的差异作用样细胞（TT1）。我们假设NP的生物反应性将与其表面化学，电荷和大小以及它们在体内相互作用细胞的功能有关。研究了胺（ANP）和羧基表面改性（CNP）和未改性（UNP）聚苯乙烯NP，其直径分别为50和100 nm。将细胞暴露于1–100μg/ ml（1.25-125μg/ cm2； 0μg/ ml对照）NP下，在37°C下有或没有抗氧化剂N-乙酰半胱氨酸（NAC）的情况下进行4和24小时。评估细胞的细胞活力，活性氧（ROS），氧化型谷胱甘肽（GSSG / GSH比），线粒体完整性，细胞形态和颗粒摄取（使用电子显微镜和激光扫描共聚焦显微镜）。ANP诱导的细胞死亡发生在所有类型的细胞中，诱导氧化应激增加，线粒体破坏和细胞色素C释放，表明凋亡性细胞死亡。尽管UNP和CNP在AT2和MACs中诱导了ROS，但它们几乎没有细胞毒性或线粒体损伤。加入NAC会减少上皮细胞ROS，但不包括MAC ROS，长达4小时。TT1和MAC细胞将所有NP格式内在化，而AT2细胞中只有一小部分将ANP内在化（而非UNP或CNP）。TT1细胞对UNP和CNP的作用最有抵抗力。ANP通过所有类型的细胞凋亡诱导明显的氧化损伤和细胞死亡，而UNP和CNP通过氧化应激表现出低细胞毒性。与AT2细胞模型相比，MAC和TT1细胞模型显示出强大的粒子内部化能力，反映了它们在体内的细胞功能。50 nm NPs在上皮细胞中诱导更高的生物反应性，而100 nm NPs对吞噬细胞显示出更强的作用。ANP通过所有类型的细胞凋亡诱导明显的氧化损伤和细胞死亡，而UNP和CNP通过氧化应激表现出低细胞毒性。与AT2细胞模型相比，MAC和TT1细胞模型显示出强大的粒子内部化能力，反映了它们在体内的细胞功能。50 nm NPs在上皮细胞中诱导更高的生物反应性，而100 nm NPs对吞噬细胞显示出更强的作用。ANP通过所有细胞类型的凋亡诱导明显的氧化损伤和细胞死亡，而UNP和CNP通过氧化应激表现出低细胞毒性。与AT2细胞模型相比，MAC和TT1细胞模型显示出强大的粒子内部化能力，反映了它们在体内的细胞功能。50 nm NPs在上皮细胞中诱导更高的生物反应性，而100 nm NPs对吞噬细胞显示出更强的作用。