The Tali®Apoptosis Kit contains:
- Annexin V – Alexa Fluor® 488 conjugate
- Annexin Binding solution
- Propidium Iodide (PI) solution
Apoptosis is a carefully regulated process of cell death that occurs as a normal part of development. Inappropriately regulated apoptosis is implicated in disease states, such as Alzheimer’s disease and cancer. Apoptosis is distinguished from necrosis by characteristic morphological and biochemical changes, including compaction and fragmentation of the nuclear chromatin, shrinkage of the cytoplasm, and loss of membrane asymmetry.
Easily Discriminate Apoptotic from Necrotic Cells with Two-color Staining
In normal live cells, phosphatidyl serine (PS) is located on the cytoplasmic surface of the cell membrane. In apoptotic cells, however, PS is translocated from the inner to the outer surface of the plasma membrane, exposing it to the extracellular environment. The human anticoagulant Annexin V displays a high affinity for PS. Annexin V labeled with a fluorophore such as Alexa Fluor® 488 can be used to identify apoptotic cells by binding to the exposed PS.
The Tali® Apoptosis Kit includes a solution of propidium Iodide (PI). PI is a cell-impermeant fluorogenic DNA-binding dye used for years to identify necrotic cells. PI is impermeant to live cells, but easily enters dead cells where it binds to nucleic acids and becomes fluorescent.
After staining a cell population using the Tali® Apoptosis Assay Kit with Annexin V-Alexa Fluor® 488 and Propidium Iodide, apoptotic cells display green fluorescence, dead cells display red and green fluorescence and live cells show little or no fluorescence.