Polymeric Nanoparticles for Delivery of Ribonucleic Acids: Overcoming the Endosomal Barrier and Going Beyond the Liver

用于传递核糖核酸的聚合物纳米颗粒：克服内体屏障并超越肝脏

• 批准号: RGPIN-2019-07243
• 负责人: Lavertu, Marc
• 金额: $ 2.04万
• 依托单位: École Polytechnique de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=753749
• 关键词: Polymeric; Nanoparticles; Delivery; Ribonucleic; Acids

Ribonucleic acid (RNA) packaged into nanoparticles (NPs) or included in molecular conjugates for delivery to cells can knock-down gene expression, elucidate gene function, express proteins, upregulate genes and edit the genome and is poised to revolutionize the field of medicine. Extensive research has been published for NP delivery systems where RNA is packaged with cationic polymers or cationic lipids. Despite significant progress achieved in the field, delivery is still the main challenge that faces RNA-based systems. Delivery systems are internalized into cells in vesicles (endosome) and entrapment in these vesicles constitutes a major intracellular barrier and a central current research problem. Additionally, delivery of RNA following intravenous administration is currently almost exclusively targeted to the liver. The applicant has an established expertise in the production and characterization of chitosan, a positively charged biopolymer composed of glucosamine that is derived from crustacean shells. Chitosan is biocompatible and is used extensively in biomedical applications. The applicant has formed NPs of chitosan with RNA and showed that these NPs are efficient in vitro and specifically accumulate in kidneys following their intravenous administration. Although these results are promising, the ability to escape the endosome, the efficacy and the biodistribution following intravenous injection of these nanosystems must be further examined and improved. A long-term objective of this research program is to develop a novel family of chitosan-based systems with increased ability to escape the endosome for improved delivery of RNA and that biodistribute to organs other than liver following intravenous administration. Another long-term objective is to further our understanding of cellular internalization and endosomal escape fundamental mechanisms. This proposal aims to extend our previous work by synthesizing a large library of chemically modified chitosans that will be used in combination with moieties facilitating endosomal release to produce entirely new delivery systems. These nanosystems will be characterized for their physicochemical and structural properties and their cellular internalization, intracellular trafficking, efficacy and biodistribution. For the first 5 years of this research program, 4 PhD students with background in polymer chemistry, colloidal science, and cell/molecular biology and 1 undergraduate student/year will be recruited. This work will provide design principles, structure-activity relationships and identify intracellular mechanisms of biological function for efficient chitosan-based RNA delivery systems and will create a knowledge base that will allow for a tremendous expansion in the applicability of these nanosystems for gene expression, gene knockdown and in vivo applications. The outcomes of this research program will be significant for the fields of gene therapy, nanotechnology and cell biology.

包装到纳米颗粒（NP）或包含在分子偶联物中以递送到细胞的核糖酸（RNA）可以敲除基因表达，阐明基因功能，表达蛋白质，上调基因并编辑基因组，并有望彻底改变医学领域。已针对NP递送系统发表了广泛的研究，其中RNA与阳离子聚合物或阳离子脂质包装。尽管该领域取得了重大进展，但交付仍然是面临基于RNA的系统的主要挑战。递送系统被内在地内化为囊泡（内体）中的细胞，这些囊泡中的夹带构成了主要的细胞内屏障和中央目前的研究问题。另外，静脉内给药后的RNA的递送目前几乎完全针对肝脏。申请人在壳聚糖的生产和表征方面具有既定的专业知识，壳聚糖是由葡萄糖胺组成的带正电荷的生物聚合物，该生物聚合物来自甲壳类壳。壳聚糖是生物相容性的，可广泛用于生物医学应用中。申请人用RNA形成了壳聚糖的NP，并表明这些NP在静脉内给药后在肾脏中有效地积聚在肾脏中。尽管这些结果是有希望的，但必须进一步检查和改进这些纳米系统后避免内体，疗效和生物分布的能力。该研究计划的一个长期目标是开发一个新型的基于壳聚糖的系统家族，具有逃脱内体以改善RNA的能力，并在静脉内给药后向肝脏以外的其他器官生物分布。另一个长期目标是进一步了解我们对细胞内在化和内体逃生基本机制的理解。该提案旨在通过合成大型化学修饰的壳聚糖库来扩展我们以前的工作，这些壳聚糖将与促进内体释放的部分结合使用，以生成全新的输送系统。这些纳米系统的特征是其物理化学和结构特性及其细胞内部化，细胞内运输，功效和生物分布。在该研究计划的前5年中，将招募4位具有聚合物化学，胶体科学和细胞/分子生物学背景的博士学位学生，并将招募1名本科生/年。这项工作将提供设计原理，结构活性关系，并确定生物学功能的细胞内机制，以实现有效的基于壳聚糖的RNA递送系统，并将创建一个知识库，从而可以在这些纳米系统在基因表达，基因敲低和VIVO应用中的适用性方面进行巨大扩展。该研究计划的结果对于基因治疗，纳米技术和细胞生物学领域至关重要。