The delivered dose: Applying particokinetics to in vitro investigations of nanoparticle internalization by macrophages
The delivered dose: Applying particokinetics to in vitro investigations of nanoparticle internalization by macrophages
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DOI：
10.1016/j.jconrel.2012.07.019
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发表时间：
2012-09-10
影响因子：
10.8
通讯作者：
Collins, Helen
中科院分区：
文献类型：
--
作者：
Khanbeigi, Raha Ahmad;Kumar, Abhinav;Collins, Helen
目的：本研究的目的是研究纳米粒子剂量测定对体外实验结果解释的影响，涉及粒子-细胞相互作用。评价了三种不同的剂量指标：1）给药剂量（在实验开始时每体积培养基施用的颗粒质量、数量或表面积），2）递送剂量（在实验持续时间内通过扩散和沉降到达细胞单层的颗粒质量、数量或表面积）和3）细胞剂量（在实验过程中被细胞内化的颗粒质量、数量或表面积）。使用体外沉降和扩散及剂量测定模型（ISDD）计算细胞培养基中的颗粒沉降和扩散，以预测递送剂量值。这些进行了比较与管理的剂量和实验确定的细胞dosevalue.Methods：给药条件和预测的递送剂量值进行了计算，在硅使用ISDD。通过将直径为50、100、200、700和1000 nm的荧光标记的聚苯乙烯珠暴露于J774A.1巨噬细胞样细胞并通过荧光光谱法测定内化颗粒含量（细胞剂量）来进行体外细胞缔合实验。实验重复使用脂多糖（LPS）激活和细胞松弛素D抑制phagocytosis.Results：只有一小部分（0.03-0.33%）的给药剂量是能够与细胞的所有测试的颗粒大小的相互作用。在六种不同暴露条件下，未活化J774A.1细胞中测得的细胞剂量与所有粒度测试的计算递送剂量值一致。当细胞剂量平均化并归一化至其相应的递送剂量时，细胞相关颗粒的百分比值为：36 +/- 10%（50）（nm）、15 +/- 3%（100）（nm）、22 +/- 6%（200）（nm）、18 +/- 4%（700）（nm）和42 +/- 19%（1000）（nm）。用LPS激活J774A.1细胞显著增加细胞剂量，在除50 nm外的所有颗粒尺寸中，细胞松弛素D处理显著降低了100、200和1000 nm颗粒的细胞剂量（标准化为递送剂量）。这项研究表明，使用ISDD模型的剂量校正（即，将细胞剂量值归一化为递送剂量）对于准确解释体外颗粒-细胞相互作用研究（例如，G.颗粒摄取、细胞毒性、作用机制、药效学研究等）。它与微粒药物递送系统领域特别相关，因为用作药物载体的大多数生物材料的低密度性质将导致在最常用的实验条件下，所施用的颗粒剂量的非常低的分数到达细胞单层。(C)2012年爱思唯尔B。V.保留所有权利。
Purpose: The aim of this study was to investigate the impact of nanoparticle dosimetry on the interpretation of results from in vitro experiments involving particle-cell interactions. Three different dose metrics were evaluated: 1) The administered dose (particle mass, number or surface area administered per volume media at the onset of an experiment), 2) the delivered dose (particle mass, number or surface area to reach the cell monolayer via diffusion and sedimentation over the duration of an experiment) and 3) the cellular dose (particle mass, number or surface area internalized by the cells during the experiment). The In Vitro Sedimentation and Diffusion and Dosimetry model (ISDD) was used to calculate particle sedimentation and diffusion in cell culture media to predict delivered dose values. These were compared with administered doses and experimentally determined cellular dose values.Methods: Dosing conditions and predicted delivered dose values were computed in silico using ISDD. In vitro cell association experiments were performed by exposing fluorescently labelled polystyrene beads of 50, 100, 200, 700 and 1000 nm diameter to J774A.1 macrophage-like cells and determining the internalized particle content (cellular dose) via fluorescence spectroscopy. Experiments were repeated using lipopolysachharide (LPS) to activate and cytochalasin D to inhibit phagocytosis.Results: Only a small fraction (0.03-0.33%) of the administered dose was able to interact with the cells for all particle sizes tested. Measured cellular doses in non-activated J774A.1 cells corresponded well with computed delivered dose values for all particle sizes tested under six different exposure conditions. When cellular doses were averaged and normalized to their corresponding delivered doses, the percentage values of cell-associated particles were: 36 +/- 10%(50) (nm), 15 +/- 3%(100) (nm), 22 +/- 6%(200) (nm), 18 +/- 4%(700) (nm), and 42 +/- 19% (1000) (nm). Activation of J774A.1 cells with LPS significantly increased the cellular dose (normalized to the delivered dose) in all particle sizes except 50 nm, while cytochalasin D treatment significantly reduced the cellular dose of 100, 200 and 1000 nmparticles.Conclusions: This study demonstrates that dose correction using the ISDD model (i.e. normalization of cellular dose values to the delivered dose) is essential for accurate interpretation of results derived from in vitro particle-cell interaction studies (e. g. particle uptake, cytotoxicity, mechanisms of action, pharmacodynamic studies, etc.). It is of particular relevance to the field of particulate drug delivery systems, because the low density nature of most biomaterials used as drug carriers will result in very low fractions of the administered particle dose reaching the cell monolayer under most commonly used experimental conditions. (C) 2012 Elsevier B. V. All rights reserved.