Purpose

Endothelial cell (EC) dysfunction underlies the pathology of multiple disease conditions including cardiovascular and pulmonary diseases. Dysfunctional ECs have a distinctive gene expression profile compared to healthy ECs. RNAi therapy is a powerful therapeutic approach that can be used to silence multiple genes of interests simultaneously. However, the delivery of RNAi to ECs in vivo continues to be a major challenge. Here, we optimized a polymer formulation based on poly(β-amino ester)s (pBAEs) to deliver siRNA to vascular ECs.

Methods

We developed a library of bioinspired oligopeptide-modified pBAE nanoparticles (NPs) with different physicochemical proprieties and screened them for cellular uptake and efficacy of RNAi delivery in vitro using ECs, vascular smooth muscle cells, and THP-1 monocytes. From the screening, the lysine-/histidine-oligopeptide modified pBAE (C6-KH) NP was selected and further tested ex vivo using mouse aorta and in mice to determine efficiency of siRNA delivery in vivo.

Results

The in vitro screening study showed that C6-KH was most efficient in delivering siRNA to ECs. Ex vivo study showed that C6-KH nanoparticles containing siRNAs accumulated in the endothelial layer of mouse aortas. In vivo study showed that C6-KH nanoparticles carrying siICAM2 injected via tail-vein in mice significantly reduced ICAM2 level in the artery endothelium (55%), lung (52%), and kidney (31%), but not in the liver, heart, and thymus, indicating a tissue-specific delivery pattern.

Conclusions

We demonstrate that C6-KH pBAE can used for delivery of siRNAs to the artery endothelium and lung, while minimizing potential side or toxic effects in the liver and heart.

中文翻译：

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使用赖氨酸/组氨酸寡肽修饰的聚（β-氨基酯）纳米颗粒将 siRNA 递送至体内内皮细胞

目的

内皮细胞 (EC) 功能障碍是多种疾病的病理基础，包括心血管和肺部疾病。与健康的 ECs 相比，功能失调的 ECs 具有独特的基因表达谱。RNAi 疗法是一种强大的治疗方法，可用于同时沉默多个感兴趣的基因。然而，在体内将 RNAi 传递到 ECs仍然是一个重大挑战。在这里，我们优化了基于聚（β-氨基酯）（pBAE）的聚合物配方，以将 siRNA 递送至血管 EC。

方法

我们开发了一个具有不同物理化学性质的仿生寡肽修饰 pBAE 纳米粒子 (NPs) 库，并使用 EC、血管平滑肌细胞和 THP-1 单核细胞筛选它们的细胞摄取和体外RNAi 递送的功效。从筛选中，选择了赖氨酸-/组氨酸-寡肽修饰的 pBAE (C6-KH) NP，并使用小鼠主动脉和小鼠进行离体进一步测试，以确定体内siRNA 递送的效率。

结果

在体外筛选研究表明，C6-KH是最有效的siRNA递送到内皮细胞。离体研究表明，含有 siRNA 的 C6-KH 纳米颗粒在小鼠主动脉的内皮层中积累。体内研究表明，通过尾静脉注射携带 siICAM2 的 C6-KH 纳米粒子在小鼠体内显着降低了动脉内皮 (55%)、肺 (52%) 和肾脏 (31%) 中的ICAM2水平，但在肝脏中没有。心脏和胸腺，表明组织特异性递送模式。

结论

我们证明 C6-KH pBAE 可用于将 siRNA 递送到动脉内皮和肺，同时最大限度地减少肝脏和心脏中的潜在副作用或毒性作用。