Phosphatidyl Serine (PS) Exposing Red Blood Cells
Phosphatidyl serine (PS) exposure has been shown to be increased in disease states such as sickle cell anemia and thalassemia.
A sample of erythrocytes is incubated with a fluorescently labeled dimer of the annexin V molecule, which binds specifically to PS in the presence of calcium. Any fluorescent events detected by flowcytometry are determined to expose PS and are counted as positive events.
A: Phosphatidyl serine exposing sickle cells labeled with fluorescent annexin V (AV). B:PS exposing red cells represented as the percent of the population that binds annexin V for sickle cell disease patients (SS) and normal controls (AA).