Dynamic and label-free cell-based assays using the real-time cell electronic sensing system.

Cell-based assays have become an integral part of the preclinical drug development process. Recently, noninvasive label-free cell-based assay technologies have taken center stage, offering important and distinct advantages over and in addition to traditional label-based endpoint assays. Dynamic monitoring of live cells, the preclusion of label, and kinetics are some of the fundamental features of cell-based label-free technologies. In this article we will discuss the real-time cell electronic sensing (RT-CES, ACEA Biosciences Inc., San Diego, CA) system and some of its key applications for cell-based assays such as cell proliferation and cytotoxicity, functional assays for receptor-ligand analysis, cell adhesion and spreading assays, dynamic monitoring of endothelial barrier function, and dynamic monitoring of cell migration and invasion. Also, where appropriate we will briefly discuss other label-free technologies in an application-specific manner.