Merocyanine 540 recognizes membrane abnormalities of erythrocytes in chronic myelogenous leukemia

Merocyanine 540 is a fluorescent dye which stains erythrocytes that have lost their normal membrane phospholipid asymmetry. Because erythrocytes from patients with chronic myelogenous leukemia have been reported to display this abnormal phenotype, peripheral blood erythrocytes from such patients were examined for their ability to stain with the dye. Erythrocytes from all patients with active disease states stained, whereas neither erythrocytes from normal, healthy individuals nor from a patient whose disease symptoms were eliminated by chemotherapy stained. These results suggest that merocyanine 540 may have utility in the clinical evaluation of chronic myelogenous leukemia.