Live Cell in Vitro and in Vivo Imaging Applications: Accelerating Drug Discovery

Abstract

Dynamic regulation of specific molecular processes and cellular phenotypes in live cell systems reveal unique insights into cell fate and drug pharmacology that are not gained from traditional fixed endpoint assays. Recent advances in microscopic imaging platform technology combined with the development of novel optical biosensors and sophisticated image analysis solutions have increased the scope of live cell imaging applications in drug discovery. We highlight recent literature examples where live cell imaging has uncovered novel insight into biological mechanism or drug mode-of-action. We survey distinct types of optical biosensors and associated analytical methods for monitoring molecular dynamics, in vitro and in vivo. We describe the recent expansion of live cell imaging into automated target validation and drug screening activities through the development of dedicated brightfield and fluorescence kinetic imaging platforms. We provide specific examples of how temporal profiling of phenotypic response signatures using such kinetic imaging platforms can increase the value of in vitro high-content screening. Finally, we offer a prospective view of how further application and development of live cell imaging technology and reagents can accelerate preclinical lead optimization cycles and enhance the in vitro to in vivo translation of drug candidates.

Intravital FLIM-FRET Imaging Reveals Dasatinib-Induced Spatial Control of Src in Pancreatic Cancer

“…To improve upon the current high attrition rates and latestage failure in drug development, more innovative and informative approaches to candidate drug selection and clinical design are required (44). Failure to translate drug candidates into clinical benefit suggest that conventional early drug discovery strategies and preclinical models are suboptimal and may poorly predict the heterogeneous drug response to effectively guide clinical dosing or combination strategies (45).…”

“…Detailed topologic analysis at cellular and subcellular resolution in live tumor tissue has enabled precise detection and single cell quantification of subtle changes in protein activity over time that cannot faithfully be achieved using standard fixed endpoint approaches applied to in vitro cultured models or ex vivo immunohistochemical analysis (2,44). Using a genetically engineered model of pancreatic cancer that recapitulates the human disease and a novel therapeutic with shown activity in pancreatic cancer, we have quantified the improvement in drug response associated with combination therapy and illustrate the application and advantages of FLIM-FRET in the drug target validation process.…”

“…Advances in systems biology approaches to drug discovery consider the complexity of disease and offer alternative strategies for target selection, validation, and drug profiling (44,45). In the fluorescence lifetime imaging field, advances have led to Figure 7.…”

Cells on film – the past and future of cinemicroscopy

“…Pharmaceutical research and development increasingly involves high-content phenotypic screening of compounds examining numerous cellular parameters by live imaging. This approach requires the use of an automated microscope placed within an environmental chamber allowing for high-throughput analysis of molecular and cell dynamics in thousands of cells placed within multi-well plates (a kinetic imaging platform in pharmaceutical jargon) (Carragher et al, 2012;Isherwood et al, 2011). Again, image processing algorithms are crucial in these screens as it would be impossible to analyse so many samples by eye.…”

In situ imaging of quantum dot-AZD4547 conjugates for tracking the dynamic behavior of fibroblast growth factor receptor 3

“…[1][2][3] Although several promising studies have suggested using in situ cellular imaging as a tool, 4,5 investigating the interaction between target proteins and drugs using this tool remains difficult due to a lack of resolution and throughput. Hence, a new probe must be introduced for in situ cellular imaging to become a major process in new drug development.…”