Laboratory for General Biochemistry and Physical Pharmacy, Faculty of Pharmacy, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
Department of Electron Microscopy, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
J Control Release. 2015 May 28;206:177-86. doi: 10.1016/j.jconrel.2015.03.015. Epub 2015 Mar 17.
Inhalation therapy with small interfering RNA (siRNA) is a promising approach in the treatment of pulmonary disorders. However, clinical translation is severely limited by the lack of suitable delivery platforms. In this study, we aim to address this limitation by designing a novel bioinspired hybrid nanoparticle with a core-shell nanoarchitecture, consisting of a siRNA-loaded dextran nanogel (siNG) core and a pulmonary surfactant (Curosurf®) outer shell. The decoration of siNGs with a surfactant shell enhances the colloidal stability and prevents siRNA release in the presence of competing polyanions, which are abundantly present in biofluids. Additionally, the impact of the surfactant shell on the biological efficacy of the siNGs is determined in lung cancer cells. The presence of the surfactants substantially reduces the cellular uptake of siNGs. Remarkably, the lowered intracellular dose does not impede the gene silencing effect, suggesting a crucial role of the pulmonary surfactant in the intracellular processing of the nanoparticles. In order to surmount the observed reduction in cellular dose, folate is incorporated as a targeting ligand in the pulmonary surfactant shell to incite receptor-mediated endocytosis. The latter substantially enhances both cellular uptake and gene silencing potential, achieving efficient knockdown at siRNA concentrations in the low nanomolar range.
利用小干扰 RNA（siRNA）进行吸入治疗是治疗肺部疾病的一种很有前途的方法。然而，由于缺乏合适的输送平台，其临床转化受到严重限制。在本研究中，我们旨在通过设计一种具有核壳纳米结构的新型仿生混合纳米粒子来解决这一限制，该纳米粒子由负载 siRNA 的葡聚糖纳米凝胶（siNG）核和肺表面活性剂（Curosurf®）外壳组成。siNG 表面用表面活性剂修饰可以增强胶体稳定性，并防止在存在大量存在于生物流体中的竞争多阴离子的情况下释放 siRNA。此外，还确定了表面活性剂壳对肺癌细胞中 siNG 生物功效的影响。表面活性剂的存在大大降低了 siNG 的细胞摄取。值得注意的是，降低细胞内剂量不会阻碍基因沉默效果，这表明肺表面活性剂在纳米颗粒的细胞内处理中起着关键作用。为了克服观察到的细胞内剂量降低，将叶酸作为靶向配体掺入肺表面活性剂壳中，以引发受体介导的内吞作用。后者大大提高了细胞摄取和基因沉默的潜力，在 siRNA 浓度达到低纳摩尔范围内实现了有效的基因敲低。
