Efficiently detect active caspase-3 in mammalian cells undergoing apoptosis by using FITC-C6-DEVD-FMK. This reagent uses a quick and simple staining protocol that is highly sensitive and compatible with standard flow cytometers.

Caspase-3 is a proteolytic enzyme with a substrate selectivity for the peptide sequence Asp-Glu-Val-Asp (DEVD). FITC-C6-DEVD-FMK is a non-toxic, cell-permeable fluorescent substrate that irreversibly binds to activated caspase-3 in apoptotic cells. The FITC-labeled substrate can be detected with high sensitivity using flow cytometry.

Caspases are a family of proteases that play a central role in cellular apoptosis through the cleavage of select proteins, and result in the disassembly of the cell (Thornberry & Lazebnik Science, 1998). This process is switched on by pro-apoptotic signals from death receptors or stimuli such as cytotoxic reagents, which activate the initiator caspases and lead to activation of the effector caspases—caspase-3 and caspase-7 (Thornberry & Lazebnik Science, 1998). FITC-C6-DEVD-FMK is useful for screening caspase-3 inhibitors and quantifying apoptotic cells containing active caspase-3.