Detection of altered membrane phospholipid asymmetry in subpopulations of human red blood cells using fluorescently labeled annexin V

摘要: The phospholipids of the human red cell are distributed asymmetrically in bilayer membrane. In certain pathologic states, such as sickle anemia, phospholipid asymmetry is altered. Although several methods can be used to measure organization, small organizational changes have been very difficult assess. Moreover, these fail identify subpopulations cells that lost their normal asymmetry. Using fluorescently labeled annexin V flow cytometry and fluorescent microscopy, we were able quantify had populations 1 million cells. loss organization 0.1% total population could identified, individual studied by microscopy. An excellent correlation was found between fluorescence-activated sorter (FACS) analysis results using detect with phosphatidylserine (PS) on surface a PS-requiring prothrombinase assay similar Cells bound fluorescein isothiocyanate (FITC)-labeled isolated from magnetic beads covered an anti-FITC antibody. Evaluation blood samples patients anemia under oxygenated conditions demonstrated presence While only few control (0.21% +/- 0.12%, n = 8), significantly increased (P < .001) labeling observed (2.18% 1.21%, 13). We conclude may occur isolate