1-Step TUNEL Assays
Label the DNA strand breaks of late-stage apoptosis with a single buffer-and-enzyme mix. Fluorescent kits for in situ imaging and flow cytometry, plus an HRP-DAB kit for light microscopy.
TUNEL 1-Step In Situ kits in FITC, FL488, FL555, FL594 and FL647 for fixed cells and tissue sections.
One-step TUNEL flow cytometry kits in green, red and violet channels to quantify apoptotic cells across a population.
A chromogenic kit for light microscopy when fluorescence imaging is not available.
TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labelling) detects DNA fragmentation, a hallmark of late-stage apoptosis. The enzyme tags the exposed 3′-OH ends of fragmented DNA with a fluorophore or chromogen so that apoptotic nuclei can be seen and counted.
Match the kit to your instrument and to any autofluorescence in the sample.
Add the single buffer-and-enzyme mix to fixed cells or sections.
Terminal transferase tags fragmented DNA with the chosen fluorophore or HRP-DAB reporter.
Visualise by fluorescence or confocal microscopy, flow cytometry or light microscopy.
DNA fragmentation, a hallmark of late-stage apoptosis. Labelled nucleotides are added to the 3′-OH ends of broken DNA so apoptotic nuclei can be counted.
They use a single buffer-and-enzyme mix, so there is no need to prepare two separate reactions. That shortens the protocol and reduces variability.
Both emit green fluorescence at similar wavelengths, but FL488 resists fading better, which helps when the signal needs to be viewed for longer.
Cells and tissues fixed in situ, including paraffin-embedded sections. Flow cytometry kits are used with cell suspensions.