Apoptosis is a form of programmed cell death to remove unwanted, damaged, or senescent cells from tissues. In normal cells, the negative phospholipids reside on the inner side of the cellular membrane while the outer surface of the membrane is occupied by uncharged phospholipids (PS). After a cell has entered apoptosis, the negatively charged PS are transported from the inner to the outer leaflet of the plasma membrane, thus exposing PS to the external cellular environment. The human anticoagulant, Annexin V, is a 35-36 kDa Ca2+-dependent phospholipid-binding protein that has a high affinity for PS. Annexin V labeled with a fluorophore or biotin can identify apoptotic cells by binding to PS exposed on the outer leaflet.
Propidium iodide (PI) is a membrane-impermeant DNA-binding dye that is commonly used to selectively stain dead cells in a cell population. PI is excluded by live cells and early apoptotic cells, but stains necrotic and late apoptotic cells with compromised membrane integrity. PI can be excited by the 488, 532, or 546 nm laser lines, and emits red ?uorescence.
Based on Abbkine strong cell platform and advanced technology, Abbkine Annexin V Apoptosis Detection kits are generated at the right moment. Abbkine Annexin V Apoptosis Detection kit contains Annexin V labeled with Abbkine proprietary AbFluorTM dyes, which allows the identification and quantitation of apoptotic cells by flow cytometry or fluorescence microscopy. Simultaneous staining of cells with AbFluorTM dyes and propidium iodide (PI) allows the discrimination of intact cells, early apoptotic and late apoptotic or necrotic cells.
Abbkine offers a variety of Annexin V conjugates labeled with our outstanding series of AbFluorTM dyes. AbFluorTM dyes have equal or much better labeling performance than other fluorescent labeling dyes such as FITC, TRITC, Cy® dyes, Alexa Fluor® and Dylight® labeling dyes by having combined advantages in brightness, photostability, specificity and novel features ideal for in vivo imaging and flow cytometry.
Take Annexin V-AbFluorTM 488 Apoptosis Detection kit for example. The typical data is as below.