Imaging assays for viability use the same principles as population assays. Cells with compromised plasma membranes allow the influx of cell-impermeant DNA-binding dyes which fluoresce only when bound to DNA. Thus, DNA staining can be used as a viability indicator for individual cells within a population.
Imaging Mammalian Cell Viability
Membrane integrity is a commonly measured parameter in cell viability assays. Cells with compromised membranes allow entry to otherwise cell-impermeant DNA-binding dyes, and this DNA staining serves as a viability indicator for individual cells within a population.
Multi-parameter assays can detect both live and dead cells to provide a total count. They can also provide measurement of esterase activity or mitochondrial function as a corollary to viability, providing more context to determine the status of both live and dead cells.
Kits with a choice of stains are optimized for high-content screening and allow for further multiplexing with fluorescent antibody-based detection.
Hep G2 cells stained using the LIVE/DEAD® Cell Imaging Kit.
Mammalian Cell Viability Assays
Cell membranes in damaged and dying cells have increased permeability and allow the influx of dyes. Combination assays measure multiple parameters to provide more context for determining the status of both live and dead cells.
|Target||Detects membrane permeability using fluorescent DNA binding dye(s)|
|Single-color assay||Also measures esterase activity||Two-color DNA binding assay||Three-color assay for mitochondrial toxicity, cell toxicity, and total cell number|
|Readout||Dead cells fluoresce green||Active cells emit mostly green, and dead cells emit mostly red||Dead cells emit green, total cells emit red or blue; measures damaged cells and total cell number||Viability and cytotoxicity assay measuring membrane permeability and mitochondrial function, together with total cell count|
|Fluorescent label||Image-iT® DEAD Green™||Calcein-AM||Image-iT® DEAD Green™||Image-iT® DEAD Green™|
|BOBO™-3 iodide||NuclearMask™ Deep Red or Hoechst 33342||MitoTracker® Orange CMTMRos & Hoechst 33342|
|Standard filter set||FITC||FITC||FITC||FITC|
|Texas Red®||DAPI or Cy®5||DAPI or Texas Red®|
|570/602||638/686 or 350/461||350/461 and 550/580|
|Platform||Imaging||Imaging, high content||Imaging, high content||Imaging, high content|
|Format||1 vial/250 coverslips||1 kit/200 assays||1 kit/200 assays||1 kit/200 assays|
|Learn more from the Molecular Probes® Handbook