Ultrasound mediated targeted therapy for kidney disease

说明(申请人提供)：抗体可用于诊断分子成像的配基，也可用于治疗中和参与肾脏疾病发展的因素。然而，许多相关抗体的全身给药可能会导致其他器官的严重副作用。为了最大限度地减少全身暴露和集中对靶器官的疗效，我们建议开发一种新的声学激活的治疗性抗体递送载体，用于局部治疗实验性糖尿病肾病。同时靶向积累和治疗是通过利用能够1)介导靶向微泡黏附到炎症和纤维化部位，以及2)通过中和分子靶点产生治疗效果的抗体来完成的。微泡超声造影剂将靶向于肾脏疾病相关分子标志物的单抗固定在造影剂表面。针对两个靶点的抗体将被研究：P-选择素和转化生长因子-β。携带抗体的微泡将被静脉注射，并积聚在血管内表达转化生长因子-β和P-选择素的部位。低功率(非破坏性)超声造影术将被用来可视化和量化抗体包裹的微泡在肾脏内的滞留。然后，抗体将通过超声中介的微泡破坏，通过高功率超声波从微泡中释放出来。这种方法在将报告基因输送到小鼠和大鼠的血管周围组织方面表现出了有效性，尽管治疗微泡在靶点的靶向积累尚未得到证实。我们建议量化携带抗体的微泡的有效载荷，并验证与重组靶蛋白的靶向粘附性。这些微泡选择性地将抗体输送到肾组织，特别是肾小球的能力，将在糖尿病肾脏疾病的小鼠模型中使用免疫组织化学和对比增强超声成像进行检测。该项目将为临床前研究开发一种新的、高效的靶向抗体传递工具。此外，这项工作有可能转化为一种临床上可行的糖尿病肾病治疗方法。 公共卫生相关性：抗体疗法为晚期肾脏疾病提供了一种治疗方式，目前只有对症治疗可用。超声介导的微泡抗体给药是一种安全、无病毒、无创、高效的药物给药方法。这种方法将减少所需的抗体量，并针对损伤部位，而肾脏中特定的微泡保留将允许使用超声成像监测糖尿病肾脏疾病的进展。

DESCRIPTION (provided by applicant): Antibodies can be used diagnostically as ligands for molecular imaging, and also as therapeutic to neutralize factors involved in the development of kidney disease. However, the systemic administration of many relevant antibodies may lead to serious side-effects in other organs. To minimize systemic exposure and concentrate efficacy to the target organ we propose to develop a novel acoustically activated therapeutic antibody delivery vehicle for local treatment of experimental diabetic nephropathy. Simultaneous targeted accumulation and therapy is accomplished by utilizing antibodies able to 1) mediate targeted microbubble adhesion to sites of inflammation and fibrosis, and 2) produce therapeutic effects by neutralizing molecular targets. Microbubble ultrasound contrast agents will be targeted to relevant molecular markers of kidney disease by monoclonal antibodies immobilized to the surface of the agent. Antibodies against two targets will be investigated: P-selectin and TGF-beta. Antibody-bearing microbubbles will be administered intravenously and accumulate at sites of intravascular expression of TGF-beta and P-selectin. Low-power (non-destructive) contrast ultrasound imaging will be used to visualize and quantify retention of antibody-coated microbubbles within the kidney. Antibodies will then be released from the microbubbles by high power ultrasound, via ultrasound mediated microbubble destruction. This method has shown efficacy for delivering reporter genes to perivascular tissue in mice and rats, although targeted accumulation of the therapeutic microbubble at the target site has not been demonstrated. We propose quantify the payload of antibody-bearing microbubbles and verify targeted adhesion to recombinant target proteins. The ability of these microbubbles to selectively deliver antibodies to renal tissue, and specifically glomeruli, will be examined using immunohistochemistry and contrast-enhanced ultrasound imaging in a mouse model of diabetic kidney disease. This project will result in the development of a novel and efficient targeted antibody delivery tool for pre-clinical research. Additionally, this work has the potential to translate into a clinically viable method of treatment for diabetic nephropathy. Public Health Relevance: Antibody therapy offers a treatment modality for advanced kidney disease, for which only symptomatic treatment is currently available. Ultrasound-mediated microbubble antibody delivery is a safe, non-viral, non- invasive and high-efficiency method of drug-delivery. This approach would reduce the amount of antibody needed and target the site of injury, while the specific retention of microbubbles in the kidney would allow for monitoring the progression of diabetic kidney disease using ultrasound imaging.