Engineering Proteins for Reabsorption in the Renal Proximal Tubule

肾脏清除血浆中的蛋白质是导致基于蛋白质的治疗药物生物利用度降低的最重要途径之一。对于那些不能有效地被肾小球毛细血管壁的过滤装置保留，并且不能有效地从近端小管内的初级尿液中重新吸收的蛋白质，这些蛋白质通过肾脏系统损失最大。虽然一些基于蛋白质的疗法已经被设计为通过共价修饰或融合到巨大的惰性蛋白质来减少肾脏清除，但这样的修饰可能会改变对预期目标组织的治疗可用性。研究人员建议识别白蛋白中的最小表位，通过表达在近端上皮中的同源转运体受体来触发这种丰富的血浆蛋白在近端小管的有效重吸收，并利用这一信息来设计通用多肽，这些多肽可以与任何治疗性蛋白融合，通过导致其完整的重吸收来减少其肾脏清除。实验目标将利用调查人员内部的工具吗？实验室设计蛋白质，分析蛋白质与细胞和受体的相互作用，并测量细胞内蛋白质的运输过程。计算目标将利用质量传输和动力学建模方法来创建一个定量框架，用于预测蛋白质结合和内吞作用的变化将如何改善治疗生物利用度，以及如何优化设计蛋白质。此外，该项目将通过综合教育项目产生更广泛的影响，在这些项目中，研究目标背后的科学将在多种教育环境中传播给学生和教师。基于蛋白质的疗法因其精致的生物学功能和特异性而变得越来越普遍。调查人员？这项工作将对提高治疗蛋白质的疗效产生广泛的影响。事实上，模型蛋白质完整重吸收的成功工程将使这项技术能够应用于任何基于蛋白质的治疗，并为基于蛋白质的药物创造一个全新的模块化。这有可能通过提高治疗效果和患者治疗方案，以及减少与蛋白质类药物生产和管理相关的财政负担，产生巨大的社会影响。

1264807Lazzara, Matthew J. The clearance of proteins from plasma by the kidneys constitutes one of the most significant pathways leading to reduced bioavailability of protein-based therapeutics. The loss of such proteins via the renal system is greatest for proteins which are not efficiently retained by the filtration apparatus of the glomerular capillary wall and which are not efficiently reabsorbed from the primary urine within the proximal tubule. While some protein-based therapeutics have been engineered for reduced renal clearance by covalent modification or fusion to bulky inert proteins, such modifications may alter therapeutic availability to intended target tissues. The investigators propose to identify minimal epitopes within albumin that trigger the efficient proximal tubule reabsorption of this abundant plasma protein through cognate transport receptors expressed in the proximal epithelium and to use this information to engineer generic peptides that can be fused to any therapeutic protein to reduce its renal clearance by causing its intact reabsorption. The experimental aims will leverage tools within the investigators? laboratories to engineer proteins, analyze protein interactions with cells and receptors, and measure intracellular protein trafficking processes. The computational aim will leverage mass transport and kinetic modeling approaches to create a quantitative framework for predicting how changes to protein binding and endocytosis will improve therapeutic bioavailability and how to optimally engineer proteins. In addition, this project will have broader impact through integrated educational programs in which the science behind the research objectives will be disseminated to students and teachers in multiple educational settings.Protein-based therapeutics are becoming increasingly common due to their exquisite biological functions and specificities. The investigators? work will have broad implications for enhancing therapeutic protein efficacy. Indeed, the successful engineering of the intact reabsorption of model proteins will enable the application of this technology to any protein-based therapeutic and create a fundamentally new modularity for protein-based drugs. This has potential for tremendous societal impact through enhancement of therapeutic efficacy and patient treatment regimens, as well as reduction in the financial burden associated with production and administration of protein-based drugs.