Cell proliferation, cell death, and apoptosis assays are cornerstones of cancer therapeutic, developmental biology, and drug safety research. Correspondingly, there are many in vitro assay methodologies for performing these assays. It has been well documented, however, that existing assays exhibit drug concentration and exposure dependencies that are difficult to interpret using single time point measurement protocols.
Surprisingly, to date there is no easy-to-use, industrialized method for quantifying the number of cells and the number of apoptotic cells (or dying cells) in the same culture continuously over time. Moreover, the growing awareness of the complexity of the tumor microenvironment and the importance of cell-to-cell signaling in cancer biology support the need to measure these parameters using more sophisticated in vitro models in which multiple cells types are present.
Biochemical techniques for measuring cell proliferation responsive to LDH, ATP, or MTS reduction are generally homogeneous plate-reader assays. While simple, these assays are limited to quantifying a bulk response, typically from a monoculture, at a single time point.
High-content imaging techniques involving immunocytochemistry and/or chemical probes can measure multiple parameters on multiple cell types. However, the labeling and read-out methods employed in such systems are quite often invasive, especially when applied to long-term, repetitive, time-lapse measurements on the same cell population.
Essen BioScience’s IncuCyte ZOOM™ (live cell imaging in your incubator) and CellPlayer™ reagents provide an easy-to-use solution to these challenges. This solution is defined by the acquisition, analysis, and quantification of images from living cells that remain unperturbed by the detection method, allowing for repeated measures of cell biology over long periods of time, from days to weeks. We refer to this solution as Live Content Imaging.