Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, USA.
Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75080, USA.
J Mater Chem B. 2023 Aug 2;11(30):7126-7133. doi: 10.1039/d3tb00696d.
Intracellular targeting is essential for the efficient delivery of drugs and nanotherapeutics. Transporting nanomaterials into cells' cytoplasm for therapeutic purposes can be challenging due to the endosomal trap and lysosomal degradation of cargo. To overcome this issue, we utilized chemical synthesis to design a functional carrier that can escape the endosome and deliver biological materials into the cytoplasm. We synthesized a thiol-sensitive maleimide linker that connects the well-known mitochondria targeting lipophilic triphenylphosphonium cation (TPP) to the surface of a proteinaceous nanoparticle based on the engineered virus-like particle (VLP) Qβ. TPP facilitates endosomal escape by its lipophilic and cationic nature, which disrupts the endosomal membrane. Once in the cytosol, glutathione reacts with the thiol-sensitive maleimide linkers, severs the TPP from the nanoparticle, halting its trafficking to the mitochondria, and marooning it in the cytosol. We successfully demonstrated cytosolic delivery of a VLP loaded with Green Fluorescent Protein (GFP) and small-ultrared fluorescent protein (smURFP) , where evenly distributed fluorescence is observed in A549 human lung adenocarcinoma cells and the epithelial cells of BALB/c mice lungs. As a proof of concept, we encapsulated luciferase-targeted siRNA (siLuc) inside the VLP decorated with the maleimide-TPP (M-TPP) linker. We observed enhanced luminescence silencing in luciferase-expressing HeLa cells using our sheddable TPP linker compared to control VLPs.
细胞内靶向对于药物和纳米治疗剂的高效递送至关重要。为了治疗目的将纳米材料输送到细胞质中可能具有挑战性，因为货物会被内体捕获和溶酶体降解。为了解决这个问题，我们利用化学合成设计了一种功能性载体，可以逃避内体并将生物材料递送到细胞质中。我们合成了一种硫醇敏感的马来酰亚胺连接物，将众所周知的靶向线粒体的亲脂三苯基膦阳离子（TPP）连接到基于工程病毒样颗粒（VLP）Qβ的蛋白质纳米颗粒的表面。TPP 通过其亲脂性和阳离子性质促进内体逃逸，破坏内体膜。一旦进入细胞质，谷胱甘肽与硫醇敏感的马来酰亚胺连接物反应，将 TPP 从纳米颗粒上切断，停止其向线粒体的运输，并将其困在细胞质中。我们成功地证明了负载绿色荧光蛋白（GFP）和小超红荧光蛋白（smURFP）的 VLP 的细胞质递送，在 A549 人肺腺癌细胞和 BALB/c 小鼠肺上皮细胞中观察到均匀分布的荧光。作为概念验证，我们将靶向荧光素的 siRNA（siLuc）封装在带有马来酰亚胺-TPP（M-TPP）连接物的 VLP 中。与对照 VLP 相比，我们观察到用可脱落的 TPP 连接物修饰的 VLP 表达荧光素的 HeLa 细胞中的发光沉默增强。
