Aouadi Myriam, Tesz Gregory J, Nicoloro Sarah M, Wang Mengxi, Chouinard My, Soto Ernesto, Ostroff Gary R, Czech Michael P
Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
Nature. 2009 Apr 30;458(7242):1180-4. doi: 10.1038/nature07774.
Gene silencing by double-stranded RNA, denoted RNA interference, represents a new paradigm for rational drug design. However, the transformative therapeutic potential of short interfering RNA (siRNA) has been stymied by a key obstacle-safe delivery to specified target cells in vivo. Macrophages are particularly attractive targets for RNA interference therapy because they promote pathogenic inflammatory responses in diseases such as rheumatoid arthritis, atherosclerosis, inflammatory bowel disease and diabetes. Here we report the engineering of beta1,3-D-glucan-encapsulated siRNA particles (GeRPs) as efficient oral delivery vehicles that potently silence genes in mouse macrophages in vitro and in vivo. Oral gavage of mice with GeRPs containing as little as 20 microg kg(-1) siRNA directed against tumour necrosis factor alpha (Tnf-alpha) depleted its messenger RNA in macrophages recovered from the peritoneum, spleen, liver and lung, and lowered serum Tnf-alpha levels. Screening with GeRPs for inflammation genes revealed that the mitogen-activated protein kinase kinase kinase kinase 4 (Map4k4) is a previously unknown mediator of cytokine expression. Importantly, silencing Map4k4 in macrophages in vivo protected mice from lipopolysaccharide-induced lethality by inhibiting Tnf-alpha and interleukin-1beta production. This technology defines a new strategy for oral delivery of siRNA to attenuate inflammatory responses in human disease.
由双链RNA介导的基因沉默，即RNA干扰，为合理药物设计提供了一种新的范例。然而，小干扰RNA（siRNA）具有变革性的治疗潜力却因一个关键障碍而受阻——在体内安全递送至特定靶细胞。巨噬细胞是RNA干扰治疗特别有吸引力的靶标，因为它们在类风湿性关节炎、动脉粥样硬化、炎症性肠病和糖尿病等疾病中促进致病性炎症反应。在此，我们报告了β1,3 - D - 葡聚糖包裹的siRNA颗粒（GeRPs）的工程设计，其作为高效的口服递送载体，能在体外和体内有效沉默小鼠巨噬细胞中的基因。给小鼠口服灌胃含有低至20微克/千克（-1）针对肿瘤坏死因子α（Tnf - α）的siRNA的GeRPs，可使从腹膜、脾脏、肝脏和肺中回收的巨噬细胞中的信使RNA减少，并降低血清Tnf - α水平。用GeRPs对炎症基因进行筛选发现，丝裂原活化蛋白激酶激酶激酶激酶4（Map4k4）是细胞因子表达的一个此前未知的调节因子。重要的是，在体内使巨噬细胞中的Map4k4沉默可通过抑制Tnf - α和白细胞介素 - 1β的产生保护小鼠免受脂多糖诱导的致死性。这项技术定义了一种口服递送siRNA以减轻人类疾病炎症反应的新策略。
