ImmunoChemistry Technologies FLIVO in vivo inhibitors and tracers

ImmunoChemistry Technologies’ FLIVO (FLuorescence in vIVO) probes are non-cytotoxic fluorescent inhibitors of caspases and contain the preferred binding sequence for many caspases, allowing researchers to assess in vivo detection of caspase-mediated apoptosis in living animals.

FLIVO is a cell-permeant reagent that readily diffuses in and out of all cells that it encounters as it circulates through the body. If there are active caspase enzymes inside a cell, FLIVO will form an irreversible covalent bond with a reactive cysteine on the large subunit of the caspase heterodimer, thereby inhibiting further enzymatic activity. The bound FLIVO probe will remain inside the cell as long as the cell membrane is intact. Any unbound FLIVO is removed from the circulation of the animal. Apoptotic cells will retain a higher concentration of FLIVO and fluoresce brighter than non-apoptotic cells, and will also detect naturally occurring, low-level apoptosis.

FAM-FLIVO and SR-FLIVO are injectable inhibitors for labelling active caspases in tissues and can be detected using a window chamber system, or tissues can be excised and analysed by flow cytometry, fluorescence microscopy or fluorescence plate reader. NIR-FLIVO are injectable tracers for labelling caspase activity in whole animals, which utilise near-infrared fluorescent labels for non-invasive detection of active caspases using whole animal imagers.