Nag Okhil K, Naciri Jawad, Oh Eunkeu, Spillmann Christopher M, Delehanty James B
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory , Code 6900, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
Bioconjug Chem. 2016 Apr 20;27(4):982-93. doi: 10.1021/acs.bioconjchem.6b00042. Epub 2016 Mar 22.
A main goal of bionanotechnology and nanoparticle (NP)-mediated drug delivery (NMDD) continues to be the development of novel biomaterials that can controllably modulate the activity of the NP-associated therapeutic cargo. One of the desired subcellular locations for targeted delivery in NMDD is the plasma membrane. However, the controlled delivery of hydrophobic cargos to the membrane bilayer poses significant challenges including cargo precipitation and lack of specificity. Here, we employ a liquid crystal NP (LCNP)-based delivery system for the controlled partitioning of a model dye cargo from within the NP core into the plasma membrane bilayer. During synthesis of the NPs, the water-insoluble model dye cargo, 3,3'-dioctadecyloxacarbocyanine perchlorate (DiO), was efficiently incorporated into the hydrophobic LCNP core as confirmed by multiple spectroscopic analyses. Conjugation of a PEGylated cholesterol derivative to the NP surface (DiO-LCNP-PEG-Chol) facilitated the localization of the dye-loaded NPs to lipid raft microdomains in the plasma membrane in HEK 293T/17 cell. Analysis of DiO cellular internalization kinetics revealed that when delivered as a LCNP-PEG-Chol NP, the half-life of DiO membrane residence time (30 min) was twice that of free DiO (DiO(free)) (15 min) delivered from bulk solution. Time-resolved laser scanning confocal microscopy was employed to visualize the passive efflux of DiO from the LCNP core and its insertion into the plasma membrane bilayer as confirmed by Förster resonance energy transfer (FRET) imaging. Finally, the delivery of DiO as a LCNP-PEG-Chol complex resulted in the attenuation of its cytotoxicity; the NP form of DiO exhibited ∼30-40% less toxicity compared to DiO(free). Our data demonstrate the utility of the LCNP platform as an efficient vehicle for the combined membrane-targeted delivery and physicochemical modulation of molecular cargos using lipid raft-mediated tethering.
生物纳米技术和纳米颗粒介导的药物递送（NMDD）的一个主要目标仍然是开发能够可控地调节与纳米颗粒相关的治疗性药物活性的新型生物材料。NMDD中靶向递送的理想亚细胞位置之一是质膜。然而，将疏水性药物可控地递送至膜双层面临重大挑战，包括药物沉淀和缺乏特异性。在此，我们采用基于液晶纳米颗粒（LCNP）的递送系统，用于将模型染料药物从纳米颗粒核心可控地分配到质膜双层中。在纳米颗粒的合成过程中，通过多次光谱分析证实，水不溶性模型染料药物3,3'-二辛基氧杂羰花青高氯酸盐（DiO）被有效地掺入到疏水性LCNP核心中。将聚乙二醇化胆固醇衍生物缀合到纳米颗粒表面（DiO-LCNP-PEG-Chol）有助于将负载染料的纳米颗粒定位到HEK 293T/17细胞的质膜中的脂筏微区。DiO细胞内化动力学分析表明，当作为LCNP-PEG-Chol纳米颗粒递送时，DiO膜停留时间的半衰期（30分钟）是从本体溶液中递送的游离DiO（DiO(free)）（15分钟）的两倍。采用时间分辨激光扫描共聚焦显微镜来可视化DiO从LCNP核心的被动流出及其插入质膜双层，这通过Förster共振能量转移（FRET）成像得到证实。最后，将DiO作为LCNP-PEG-Chol复合物递送导致其细胞毒性减弱；与DiO(free)相比，DiO的纳米颗粒形式表现出约30-40%的较低毒性。我们的数据证明了LCNP平台作为一种有效载体的实用性，该载体可通过脂筏介导的拴系实现分子药物的联合膜靶向递送和物理化学调节。
