Collaborative Research: Impedance-Enabled Microfluidic Renal Proximal Tubule Biochip Platform

为了研究药物或其他治疗方法对人体肾脏的负面影响，已经开发了筛选方法来评估临床前试验期间的潜在毒性。尽管目前有临床前筛查的方法，但在临床实践中，药物毒性引起的肾损伤的发生率仍然高得令人无法接受，占所有急性肾损伤发作的近20%。迄今为止，早期确定药物毒性的一个主要限制是依赖于动物实验，而动物对药物的反应往往不能预测人类的反应。该项目旨在开发创新的设备和方法，将人类肾脏细胞的培养与微流体系统中基于阻抗（一种复杂形式的电阻）的传感技术相结合。这些微流体系统将被开发用于复制研究药物对人体肾脏毒性所需的生理行为，从而作为一种先进的药物筛选方法，具有提高准确性和降低成本的潜力。该研究独特的跨学科性质提供了丰富的教育机会。K-12学生、本科生和研究生，包括女性和代表性不足的群体，将通过旨在培养对科学和工程兴趣的多个项目，参与药物筛选系统的开发。本项目重点开发微流体近曲管生物芯片，作为药物开发过程中药物临床前毒理学筛选的体外模型。为了提高筛选过程的效率和降低成本，将开发和验证嵌入人肾细胞的微流控芯片。为了模拟近端小管，生物芯片将被开发，其特征是在这种双层微流体装置中有一个中央的、有地形图案的多孔膜。基于阻抗传感的组件将使用微加工技术集成到该系统中。人肾近端小管上皮细胞（hRPTEC）和人微血管内皮细胞（hMVEC）将在芯片上共同培养和维持，形成药物在肾脏中主动清除、重吸收、细胞内浓度和积累的主要位点。随着时间的推移，共培养细胞将暴露于一系列众所周知的不同浓度的肾毒素中。对于每次暴露，模型细胞的阻抗谱将被记录和校准，利用来自传统毒性和细胞活力评估的细胞损伤数据。除了应用于体外肾脏模型之外，将阻抗传感技术与这些系统集成所获得的见解可能广泛应用于各种“器官芯片”技术以及无数基于细胞的生物传感器和“芯片实验室”设备。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In order to study the negative effects of drugs or other therapeutics on human kidneys, screening methods have been developed to evaluate potential toxicity during preclinical testing. Despite current methods for preclinical screening, the occurrence of kidney injury due to drug toxicity in clinical practice remains unacceptably high, accounting for nearly 20% of all episodes of acute kidney injury. To date, a major limitation in the early determination of the toxicity of drugs is the reliance on experiments in animals whose responses to drugs often cannot predict human responses. This project aims to develop innovative devices and methods that combine the culturing of human kidney cells and impedance (a complex form of resistance)-based sensing techniques in a microfluidic system. These microfluidic systems will be developed to replicate the physiological behavior needed for studying the toxicity of drugs upon the human kidney, thus serving as an advanced drug screening method with the potential for increased accuracy and lower cost. The unique interdisciplinary nature of the research provides rich educational opportunities. K-12 students along with undergraduate and graduate students, including women and underrepresented groups, will be included in the development of the drug screening system through multiple programs designed to foster interest in science and engineering. This project focuses on the development of microfluidic proximal convoluted tubule biochips as in vitro models for preclinical toxicology screening of drugs in the pharmaceutical development process. To improve the efficiency and decrease the costs associated with the screening process, microfluidic chips imbedded with human kidney cells will be developed and validated. To simulate the proximal tubule, biochips will be developed featuring a central, topographically patterned, porous membrane within this bilayer microfluidic device. Impedance sensing-based components will be integrated into this system using microfabrication techniques. Human renal proximal tubular epithelial cells (hRPTEC) and human microvascular endothelial cells (hMVEC) will be co-cultured and maintained on the chip, forming the primary sites for active clearance, reabsorption, intracellular concentration, and accumulation of drugs in the kidney. The co-cultured cells will be exposed to a series of well-known nephrotoxins of varying concentration over time. For each exposure, the impedance spectra of the model cells will be recorded and calibrated, making use of data on cell damage derived from conventional assessments of toxicity and cell viability. Beyond the application to in vitro kidney models, the insights gained from integrating impedance-sensing technology with these systems may be broadly applied towards diverse 'organ-on-a-chip' technologies as well as myriad cell-based biosensors and 'lab-on-a-chip' devices.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.