ABSTRACT

INTRODUCTION High-content screening (HCS) has evolved over the past 10 years to transform processes and techniques for fluorescence microscopy from the single representative sample on a glass slide to the fully automated high-throughput screening (HTS) process (1). This process has been embraced by microscopists and cellular biologists alike to query multiple therapeutic areas of study in order to better characterize disease processes, “on and off target” perturbances of potential target molecules as well as monitoring the impact on cellular homeostasis of silencing RNA treatments (2). Cellular biologists have integrated these autonomous platforms that can serve to industrialize the experimental process: acquiring images, performing image analysis to quantify detectable fluorescent changes of probes and biosensors, and finally, analyzing the numerical data with visualization tools to present the information in an interpretable fashion (3). HCS is often used in the drug discovery process to provide information on mechanism of action when deciphering disease states or alterations due to compound treatment and has brought many successes and enlightenments of cellular processes and pathways (4). These platforms inherently have enabled both a high-resolution, detailed view of biological processes as well as have the ability to exponentially examine tens of thousands of samples per day (5). Therefore, profiling applications where evaluations of scores of compounds or of many distinct cell types for a particular function or event have become commonplace. A significant area of study has been cellular profiling for early safety evaluations where the goal is to quantify multiple cell health parameters and cytotoxicity assessments to detect early compound liabilities (6). Analogously, profiling studies utilizing cytotoxicity read-outs for compounds with similar functions, such as kinase inhibition, have been done to characterize the kinase targets and the nonspecificity of kinase action (7). High-content imaging instrumentation and techniques are expanding to encompass the latest advancements in physics and biology to achieve submicron resolution imaging and multimodal optical properties. At present, studies such as those described here are significantly impacting the drug discovery process and its strategic approach in developing new molecules.