EAGER: A Novel Lab-on-Chip with Optical Micro-Stretch Assembly for Characterization of Stretch-Activated Cell Electrophysiology

美国国家科学基金会使用探索性研究早期概念补助金(EARGER)资助机制，支持未经检验但可能具有变革性的研究想法或方法的早期探索性工作。这个渴望的项目之所以被授予，是因为在亲爱的同事信NSF 16-080中，邀请来自历史悠久的黑人学院和大学的提倡者提交建议，以加强该机构教师的研究能力。诺福克州立大学的这一项目旨在使用一种新的光学非接触细胞拉伸方法来在生物细胞中创建受控拉伸。因此，该项目成果可以通过建模揭示心脏电异常的机制，并通过使体外可重复的拉伸条件能够从机械上表征包括心力衰竭在内的各种人类疾病，将电生理测量与机械拉伸联系起来。可兴奋的生物细胞，如心脏细胞，表现出机械-电学敏感性，通过机械刺激或拉伸来调节它们的电行为。这在心力衰竭等慢性疾病中尤其关键，在这些疾病中，增加的压力可能会导致危及生命的异常，称为心律失常。细胞中特殊的拉伸激活离子通道被认为是造成这种现象的原因。然而，这些通道的特征并不是很好，部分原因是缺乏有效的细胞伸展和同步电记录技术。在本项目中，提出了一种新的光学非接触拉伸方法，利用反向传播的激光，能够在最现实的条件下在生物细胞中产生可控的拉伸。将设计一个用于从细胞进行自动化、高通量电生理记录的微流控平台。紧密聚焦的激光束将被用来拉伸细胞，同时进行膜片钳记录。提出的光流控芯片将被用来系统地表征心肌细胞中拉伸激活的离子通道。这些实验与先进的基于计算机的建模相结合，将为心力衰竭条件下心律失常的机制提供有用的见解。细胞拉伸技术可以扩展到研究其他几种疾病，如癌症、脑瘤、帕金森病，甚至植物疾病。这个急切的项目是由工程局资助的。

The National Science Foundation uses the Early-concept Grants for Exploratory Research (EAGER) funding mechanism to support exploratory work in its early stages on untested, but potentially transformative, research ideas or approaches. This EAGER project was awarded as a result of the invitation in the Dear Colleague Letter NSF 16-080 to proposers from Historically Black Colleges and Universities to submit proposals that would strengthen research capacity of faculty at the institution. The project at Norfolk State University aims use a novel optical non-contact cell stretching method to create a controlled stretch in biological cells. Accordingly, the project outcome can unveil mechanisms governing heart electrical abnormalities via modeling and relate the electrophysiological measurements to mechanical stretching by enabling reproducible stretch conditions in vitro to mechanistically characterize various human disorders including heart failure. Excitable biological cells, such as heart cells, exhibit mechano-electric sensitivity by which their electrical behavior is modulated by mechanical stimuli or stretch. This is especially critical in chronic diseases such as heart failure where increased stress may induce life-threatening abnormalities, called arrhythmias. Specialized stretch-activated ion channels in cells are thought to be responsible for this phenomenon. However, these channels are not well characterized, partly due to a lack of efficient cell stretching and simultaneous electrical recording techniques. In this project, a novel optical non-contact stretching method, using counter-propagating laser beams, is proposed which is capable of producing a controlled stretch in biological cells in the most realistic condition. A microfluidic platform for performing automated, high throughput electrophysiological recordings from cells will be designed. Tightly focused laser beams will be used to stretch the cells while simultaneously performing the patch clamp recordings. The proposed optofluidic chip will be used to systematically characterize the stretch-activated ion channels in cardiac cells. The experiments combined with advanced computer-based modeling will provide useful insights into the mechanisms of arrhythmias in heart failure conditions. The cell-stretching technique could be extended to study several other diseases such as cancer, brain tumors, Parkinson disease and even plant disorders. This EAGER project is funded by the Engineering Directorate.