How to choose the right caspase assay for your experiments
The two main pathways through which apoptotic cell death is initiated are the intrinsic and extrinsic cell death pathways, characterized by caspase 9 and caspase 8 activation, respectively.
Assays that determine caspase activity through cleavage of biochemical substrates are a quick and convenient method to assess caspase activation in cells. However, caution is recommended when interpreting the data from these experiments.
What do I need to consider when interpreting data from caspase activity experiments?
- The substrate in a given assay is not necessarily specific to a particular caspase. As cleavage specificities of caspases overlap, relying on a single substrate/assay is not recommended for identification of a specific caspase. Best practice is to use more than one method to confirm specific caspase activation. For example, caspase 8 activity assays should be used in combination with western blot detection of uncleaved/cleaved (active) caspase 8.
- The expression and abundance of each caspase in a particular cell type and cell line will vary.
- As the activation and cleavage of caspases in the cascade will change over time, it’s important to consider the point of peak expression of the particular caspase e.g., after three hours, after 20 hours etc. Classification of caspases based on synthetic substrate preference does not reflect the true caspase substrate preference in vivo and may provide inaccurate information for discriminating amongst caspase activities. Caution is advised in applying the intrinsic tetrapeptide preferences to predict the targets of individual caspases.
Caspase cross-reactivity guide
The tables below show known cross-reactivities with other caspases.
Inflammatory caspases
Apoptotic initiator caspases
Apoptotic executor caspases
How do I measure caspase activity in cell lysates?
Our range of assays below is suitable for colorimetric and fluorometric analysis of cell lysates using a plate reader.
How our assays can help
Our broad portfolio features a comprehensive range of assays—cited in hundreds of scientific publications—for all the major caspases.
Caspase-3 Assay Kit
- Easy to use, mix-and-read Caspase-3 assay
- Simply add samples to wells, add reaction buffer and DEVD-p-NA substrate, incubate for 60-120 min at 37°C, and analyze with a colorimetric microplate reader
How do I measure caspase activity in live cells?
Our range of assays below can be used with a flow cytometer, microscope or plate reader to measure caspase activity in live cells.
How our assay kits can help
Our convenient, optimized assay kits come with everything you need to run your experiment, streamlining your workflow and saving you time.
Caspase-3/7, Caspase-8 and Caspase-9 Multiplex Activity Assay Kit (Fluorometric)
- Analyze the activity of three critical caspases in live cells in one convenient, easy-to-use assay kit
- Choose to measure the three caspases separately or together in one well
- Analyze with a microplate reader
