Annexin V Fluorochromes ( #130-093-060 #130-092-773 )

Annexin V Fluorochromes

Overview

This product is suitable for the identification and enumeration of dead cells, such as apoptotic or necrotic cells, by flow cytometry.

Details

Background information
The Annexin V Fluorochromes selectively label apoptotic, necrotic, and dead cells through the specific binding of Annexin V to phosphotidylserine (PS). In most normal, viable eukaryotic cells, the negatively charged phospholipid PS is located in the cytosolic leaflet of the plasma membrane lipid bilayer.¹ PS redistribution from the inner to the outer leaflet is an early and widespread event during apoptosis.^1,2 However, in necrosis, PS becomes accessible due to the disruption of membrane integrity.² Apart from necrosis and apoptosis, PS also becomes accessible in activated platelets³, in certain cell anomalies like sickle cell anemia⁴, in erythrocyte senescence⁵, upon degranulation of mast cells⁶, and in certain stages of B cell differentiation⁷. PS exposure by apoptotic cells serves as a trigger for the recognition and removal by macrophages.^8,9
Annexin V is a 35 kDa phospholipid-binding protein and has a high affinity for PS in the presence of physiological concentrations of calcium (Ca²⁺).¹⁰

Figure 1

Staining principle of PS-exposing cells with Annexin V-FITC.

Figure 2

Jurkat cells, cultured with staurosporine (50 nM) for 15 hours, were stained with Annexin V-FITC and analyzed by flow cytometry.

Figure 3

Jurkat cells were cultured with and without different concentrations of staurosporine (200 nM up to 2 μM) for different times (from 4 up to 20.5 hours). Cells were then pooled and stained with Annexin V-Biotin followed by Anti-Biotin-APC and PI and analyzed by flow cytometry.