Gene Delivery Agents for Ultrasound-Mediated Transfection

描述(申请人提供)：我们建议开发一种新的声学激活微泡基因传递载体，用于治疗实验性炎症性肠病。由阳离子脂壳组成的微泡超声造影剂通过固定在微泡造影剂表面的单抗靶向黏附分子MAdCAM-1。质粒DNA通过静电作用偶联到试剂的阳离子表面。微泡被静脉注射，并聚集在血管内MAdCAM-1表达的部位，对应于炎症灶。利用临床超声扫描仪，通过超声介导的微泡破坏，将DNA从靶点的试剂中释放出来。这种方法已经在小鼠和大鼠的血管周围组织中显示了报告基因的有效性。这一策略提供了一种在体内传递遗传物质的安全、非病毒、非侵入性的方法。选择性是通过将试剂靶向炎症的分子标记物来实现的，需要超声波介导的微泡破坏才能从试剂表面释放DNA。将检查这些基因输送工具的稳定性，以评估一种研究级基因输送工具用于商业规模生产的可行性。在炎症性肠病的小鼠模型中，将使用荧光素酶报告基因和生物发光成像来检验这些药物选择性地转染炎症性肠病的能力。该项目将开发一种用于临床前研究的新颖而有效的基因传递工具，它可以消除对有问题的病毒载体和侵入性电穿孔技术的需求。此外，这项工作有可能转化为临床上可行的炎症性肠病治疗方法。基因疗法为克罗恩病提供了一种治疗方式，目前只有对症治疗可用。超声介导的微泡基因转染法是一种安全、无病毒、无创、高效的基因转染法。靶向超声激活微泡基因载体的研制为临床前研究中实现基因转移提供了一种新颖而有效的方法。这项技术将提供一种替代病毒和侵入性电穿孔技术的方法，并为利用现有超声设备在临床环境中实现基因传递提供了一种潜在的模式。

DESCRIPTION (provided by applicant): We propose to develop a novel acoustically activated microbubble gene delivery vehicle for treatment of experimental inflammatory bowel disease. Microbubble ultrasound contrast agents composed of a cationic lipid shell are targeted to the adhesion molecule MAdCAM-1 by a monoclonal antibody immobilized to the surface of the agent. Plasmid DNA is coupled to the cationic surface of the agent via electrostatic interaction. Microbubbles are administered intravenously and accumulate at sites of intravascular MAdCAM-1 expression, corresponding to inflammatory foci. DNA is released from the agents at the target site by ultrasound-mediated microbubble destruction using a clinical ultrasound scanner. This method has shown efficacy for transfecting reporter genes to perivascular tissue in mice and rats. This strategy offers a safe, non-viral, non-invasive method of delivering genetic material in vivo. Selectivity is accomplished by targeting the agents to a molecular marker of inflammation, and ultrasound-mediated microbubble destruction is required for release of DNA from the agent surface. The stability of these gene delivery vehicles will be examined to assess the feasibility for commercial scale production of a research-grade tool for gene delivery. The ability of these agents to selectively transfect inflamed bowel will be examined using a luciferase reporter gene and bioluminescence imaging in a mouse model of inflammatory bowel disease. This project will result in the development of a novel and efficient gene delivery tool for pre-clinical research, which can eliminate the need for problematic viral vectors and invasive electroporation techniques. Additionally, this work has the potential to translate into a clinically viable method of treatment for inflammatory bowel disease. Gene therapy offers a treatment modality for Crohn's disease, for which only symptomatic treatment is currently available. Ultrasound-mediated microbubble gene delivery is a safe, non-viral, non-invasive and high- efficiency method of transfection. The development of targeted ultrasound-activated microbubble gene delivery vehicles presents a novel and effective method of accomplishing gene transfer in pre-clinical research. This technique will offer an alternative to viral and invasive electroporation transfection techniques, and offers a potential mode for accomplishing gene delivery in a clinical setting using existing ultrasound equipment.