RNA delivery by self-assembling phagocytic-competent protein crystals

通过自组装具有吞噬能力的蛋白质晶体进行 RNA 递送

• 批准号: 10067767
• 金额: $ 30.24万
• 依托单位: CELL GUIDANCE SYSTEMS LIMITED
• 依托单位国家: 英国
• 项目类别: Collaborative R&D
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=10067767
• 关键词: RNA; delivery; self; assembling; phagocytic

The mechanism by which a drug travels following administration (e.g. by intravenous injection) to reach its molecular target is critical to efficacy. Innovations in drug delivery have been fundamental to many medical advances. Most recently, RNA drugs, including widely used vaccines against SARS-CoV-2, have entered the market. RNA drugs required novel mechanisms of drug delivery which overcame specific challenges: Whilst conventional drugs act outside cells or are small enough to permeate through to intracellular targets, RNA drugs are only effective inside cells, and their large size necessitates a specific delivery mechanism to carry them across the cell wall and into the cell cytosol where they act.Viruses and lipid nanoparticles (LNPs, resembling small hollow spheres of fat) are used to deliver currently approved RNA drugs. Viruses and LNPs envelop and protect the RNA from damage whilst outside the cell and are able to dock or fuse with the cell wall to make the final delivery of RNA. However, these technologies have significant shortcomings including production costs, batch consistency, storage stability, immunogenicity, lack-of-targeting, the efficiency of cell entry, and endosomal escape. Whilst improvements in these technologies are being made, a fresh approach may better address these challenges.Particles access cells through a variety of passive and active mechanisms. Phagocytosis is a process in which cells actively ingest particles (most efficiently in the 0.3 - 5 microns size range). This process is particularly efficient in professional mononuclear phagocytic (MP) cells. These immune cells present vaccine antigens, ingest debris and eliminate invading pathogens. They also migrate to diseased and injured tissue and are involved in a variety of processes, including the generation of vaccine immunity, autoimmune diseases, wound healing and cancer. Some MPs, such as the liver's Kupfer cells, are not of haemopoietic origin. MPs also harbour many important pathogens. RNA drugs that effectively target MPs have the potential to impact many devastating diseases.We have engineered microscopic protein crystal particles, called PODS crystals, that contain specific bioactive protein cargos. MPs ingest PODS crystals and secrete their cargo proteins intact. We have also shown that cargo proteins enter the cytosol - the area of the cell where RNA is active - suggesting the possibility to deliver RNA. Here, we plan to generate protein crystal particles to deliver RNA to MP cells. Once this has been demonstrated, we will test RNAs' ability to modify MP cells' behaviour across a range of biomedical applications.

药物在给药（例如通过静脉注射）后到达其分子靶点的机制对于疗效至关重要。药物输送的创新是许多医学进步的基础。最近，RNA 药物，包括广泛使用的 SARS-CoV-2 疫苗，已进入市场。 RNA 药物需要新的药物递送机制来克服特定的挑战：传统药物在细胞外起作用或小到足以渗透到细胞内靶标，而 RNA 药物仅在细胞内有效，而且它们的大尺寸需要特定的递送机制来携带它们穿过细胞壁并进入细胞胞浆并在那里发挥作用。病毒和脂质纳米颗粒（LNP，类似于小的空心脂肪球）是 用于输送目前批准的RNA药物。病毒和 LNP 在细胞外包裹并保护 RNA 免受损伤，并且能够与细胞壁对接或融合以最终递送 RNA。然而，这些技术存在显着的缺点，包括生产成本、批次一致性、储存稳定性、免疫原性、缺乏靶向性、细胞进入效率和内体逃逸。虽然这些技术正在不断改进，但一种新的方法可能会更好地解决这些挑战。粒子通过各种被动和主动机制进入细胞。吞噬作用是细胞主动摄取颗粒的过程（在 0.3 - 5 微米尺寸范围内最有效）。该过程在专业单核吞噬 (MP) 细胞中特别有效。这些免疫细胞呈现疫苗抗原，吞噬碎片并消除入侵的病原体。它们还迁移到患病和受伤的组织，并参与多种过程，包括疫苗免疫力的产生、自身免疫性疾病、伤口愈合和癌症。一些MP，例如肝脏的库普弗细胞，不是造血来源的。国会议员还携带许多重要的病原体。有效靶向 MP 的 RNA 药物有可能影响许多毁灭性疾病。我们设计了微小的蛋白质晶体颗粒，称为 PODS 晶体，其中含有特定的生物活性蛋白质货物。 MP 摄取 PODS 晶体并完整地分泌其货物蛋白。我们还表明，货物蛋白进入细胞质（RNA 活跃的细胞区域），这表明了递送 RNA 的可能性。在这里，我们计划生成蛋白质晶体颗粒，将 RNA 传递到 MP 细胞。一旦这一点得到证实，我们将测试 RNA 在一系列生物医学应用中改变 MP 细胞行为的能力。