Acetylcholinesterase and lymphocyte function-associated antigen 3 found on
decay-accelerating factor-negative erythrocytes from some patients with
paroxysmal nocturnal hemoglobinuria are lost during erythrocyte aging
E Ueda, T Kinoshita, T Terasawa, T Shichishima, Y Yawata, K Inoue and T Kitani
Department of Clinical Research, Osaka University, Japan.
Erythrocytes from patients with paroxysmal nocturnal hemoglobinuria are
deficient in decay-accelerating factor (DAF), a factor called C8- binding
protein or homologous restriction factor, acetylcholinesterase (AchE), and
lymphocyte function-associated antigen 3 (LFA-3). These proteins share a
common feature that glycan-inositolphospholipid anchors the protein to the
membrane, suggesting that an abnormality related to this glycolipid causes
multiple protein deficiencies. The relationship between the DAF, AchE, and
LFA-3 defects was studied by fluorescent flow cytometric analysis. In five
patients, DAF-negative erythrocytes were also AchE-negative. In three
patients, a fraction of DAF-negative erythrocytes expressed subnormal
levels of AchE, indicating that AchE was synthesized in these DAF-negative
cells. Erythrocytes from the patients having DAF-negative, AchE-positive
cells were separated according to density and analyzed for expression of
DAF and AchE. Both proteins decreased with increase of cell density,
suggesting that DAF-negative, AchE-positive cells become AchE-negative
during erythrocyte maturation by losing AchE. A low level of LFA-3 was
found on DAF-negative erythrocytes from one patient and decreased with
erythrocyte maturation. These results support an idea that complete
deficiency of glycan-inositolphospholipid-anchored proteins on erythrocytes
could result from abnormally early termination of surface recruitment of
these proteins, and subsequent dilution through cell divisions and loss
from the surface.
Volume 75,
Issue 3,
pp. 762-769,
02/01/1990
Copyright © 1990 by The American Society of Hematology
