title: Quantitation of CD55 and CD59 expression on reticulocytes and mature erythrocytes in paroxysmal nocturnal hemoglobinuria, aplastic anemia, and healthy control subjects.
abstract: Since PNH occasionally results in bone marrow failure, it is difficult to differentiate PNH from AA with small numbers of CD(55) (-)CD(59) (-) erythrocytes. We quantified CD55 and CD59 molecules expressed on normal reticulocytes and mature erythrocytes of paroxysmal nocturnal hemoglobinuria (PNH), aplastic anemia (AA), and normal individuals in order to determine their usefulness for differentiation between PNH and AA. A total of 56 patients (AA 39 patients, PNH 17 patients) and 10 healthy volunteers were enrolled. Two-color flow cytometric analyses were conducted using thiazole orange, anti-CD55 and CD59 monoclonal antibodies to identify CD(55) (-)CD(59) (-) reticulocytes and mature erythrocytes. Mean fluorescence level of CD(55) (+) mature erythrocytes was lowest in the PNH patients (13.2 x 10(3) MESF), and was significantly lower than in normal controls (16.7 x 10(3) MESF, p <0.05), and highest in the AA subjects (22.8 x 10(3) MESF). Mean fluorescence level of CD(59) (+) mature erythrocytes was lowest in the PNH subjects (24.5 x 10(3) MESF), significantly less than in normal controls (39.0 x 10(3) MESF, p <0.05), and highest in the AA subjects (49.2 x 10(3) MESF). Total reticulocyte counts correlated strongly with the CD(55) (-)CD(59) (-) reticulocytes. Comparative quantitative analysis of CD55 and CD59 molecules expressed on normal erythrocytes may be useful in differentiating PNH from AA patients with small numbers of PNH-phenotype erythrocytes, and the total reticulocyte count may prove useful as a marker for PNH clone size.
authors.affiliation: Department of Laboratory Medicine, Catholic University Medical College, Seochogu, Seoul, Korea (south) 137-701.
authors.forename: Yeongsic
authors.initials: Y
authors.lastname: Kim
authors.forename: Jihyang
authors.initials: J
authors.lastname: Lim
authors.forename: Myungshin
authors.initials: M
authors.lastname: Kim
authors.forename: Yonggoo
authors.initials: Y
authors.lastname: Kim
authors.forename: Jong-Wook
authors.initials: JW
authors.lastname: Lee
authors.forename: Kyungja
authors.initials: K
authors.lastname: Han
mesh_terms: D000328:Adult; D000741:Anemia, Aplastic / Q000378:metabolism*; D018958:CD55 Antigens / Q000378:metabolism*; D018957:CD59 Antigens / Q000378:metabolism*; D016022:Case-Control Studies; D004906:Erythrocyte Count; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D006457:Hemoglobinuria, Paroxysmal / Q000378:metabolism*; D006801:Humans; D016130:Immunophenotyping; D008297:Male; D008875:Middle Aged; D012156:Reticulocytes / Q000378:metabolism*; D055815:Young Adult
chemical_list: D018958:CD55 Antigens; D018957:CD59 Antigens; C051590:CD59 protein, human