AAT Bioquest

How do you identify stages of apoptosis?

Posted May 18, 2020


Apoptosis can be seen as a stage-dependent process from its induction to early, intermediate and late-stage apoptotic events. Methods and reagents have been developed to identify the various apoptotic stages.

  • Early stage: Early stage apoptosis is represented by changes to, and ultimate loss of, the mitochondrial membrane potential, which can be detected by mitochondria selective dyes such as JC-1 and rhodamine 123.
  • Intermediate stage: The exposure of phosphatidylserin (PS) to the extracellular portion of the membrane is a sign for intermediate stage. Annexin V staining is used for PS detection.
  • Late stage: DNA fragmentation is seen as a marker for late stage apoptosis, where TUNEL assay can be used to detect the cleaved DNA strand.
Additional resources

Annexin-V Staining

Cell Meter™ Live Cell TUNEL Apoptosis Assay Kit *Red Fluorescence*

Fink, S. L., & Cookson, B. T. (2005). Apoptosis, Pyroptosis, and Necrosis: Mechanistic Description of Dead and Dying Eukaryotic Cells. Infection and Immunity, 73(4), 1907–1916. doi:10.1128/iai.73.4.1907-1916.2005