State Key Laboratory of Genetic Engineering, Department of Pharmaceutical Sciences, School of Life Sciences, Fudan University, Shanghai 200438, P.R. China.
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, P.R. China.
ACS Nano. 2021 May 25;15(5):8267-8282. doi: 10.1021/acsnano.0c08596. Epub 2021 Apr 29.
Cytosolic delivery of small interfering RNA (siRNA) remains challenging, and a profound understanding of the cellular uptake and intracellular processing of siRNA delivery systems could greatly improve the development of siRNA-based therapeutics. Here, we show that caveolae-mediated endocytosis (CvME) accounts for the robust siRNA delivery of mannose-modified trimethyl chitosan-cysteine/tripolyphosphate nanoparticles (MTC/TPP NPs) to macrophages by circumventing lysosomes. We show that the Golgi complex and ER are key organelles required for the efficient delivery of siRNA to macrophages in which the siRNA accumulation positively correlates with its silencing efficiency ( = 0.94). We also identify syntaxin6 and Niemann-Pick type C1 (NPC1) as indispensable regulators for MTC/TPP NPs-delivered siRNA into macrophages both and . Syntaxin6 and NPC1 knockout substantially decrease the cellular uptake and gene silencing of the siRNA delivered in MTC/TPP NPs in macrophages, which result in poor therapeutic outcomes for mice bearing acute hepatic injury. Our results suggest that highly efficient siRNA delivery can be achieved CvME, which would give ideas for designing optimal delivery vectors to facilitate the clinical translation of siRNA drugs.
细胞质内递送小干扰 RNA（siRNA）仍然具有挑战性，深入了解 siRNA 递送系统的细胞摄取和细胞内处理过程，可以极大地促进基于 siRNA 的治疗药物的发展。在这里，我们表明，笼形蛋白介导的内吞作用（CvME）通过绕过溶酶体，使甘露糖修饰的三甲基壳聚糖-半胱氨酸/三聚磷酸酯纳米粒（MTC/TPP NPs）能够有效地将 siRNA 递送至巨噬细胞。我们表明，高尔基体和内质网是将 siRNA 有效递送至巨噬细胞所必需的关键细胞器，其中 siRNA 的积累与沉默效率呈正相关（=0.94）。我们还发现，网格蛋白 6 和尼曼-匹克 C1（NPC1）是 MTC/TPP NPs 递送至巨噬细胞中 siRNA 的不可或缺的调节剂，无论是内吞作用还是胞吐作用。网格蛋白 6 和 NPC1 的敲除会显著降低巨噬细胞中 MTC/TPP NPs 递送的 siRNA 的细胞摄取和基因沉默，从而导致急性肝损伤小鼠的治疗效果不佳。我们的结果表明，可以通过 CvME 实现高效的 siRNA 递送，这为设计最佳递送载体以促进 siRNA 药物的临床转化提供了思路。
