Multiparameter flow cytometry analysis of peripheral blood in PNH. (A-D) Aplastic anemia patient with small (2%) PNH clone; (E-H) classic PNH patient. (A,E) Forward scatter (FSC)/side scatter (SSC) display showing initial gate to exclude lymphocytes and debris. (B,F) Granulocytes (green) are identified as bright CD15 and low CD33, whereas monocytes (blue) are bright CD33 and low CD15. (C,G) Population of GPI anchor protein–deficient granulocytes showing lack of staining with both anti-CD24 and FLAER. (D,H) Population of GPI anchor protein–deficient monocytes showing lack of staining with both anti-CD14 and FLAER.