Cell health assays provide a simple way to measure various parameters of living, dead or dying cells. Kits are available for measuring cell viability and cytotoxicity, anchorage-dependent cell death, cellular senescence, cell proliferation and cellular hypoxia.
Measurements of cell viability and cytotoxicity are widely used to study the effects of growth factors and cytokines, inhibitors and activators, as well as immune response signals.
Many viability and toxicity test kits (such as XTT, resazurin and BrdU kits) monitor the presence or viability of living cells by measuring the metabolic conversion or incorporation of a substrate into cell molecules.
Assay kits that measure dead or dying cells are usually based on the activity of apoptotic enzymes (i.e., caspase-3) or the intracellular release of an enzyme or molecule indicative of cell death (e.g. that is, cytochrome c, LDH).