Increased erythrocyte phosphatidylserine exposure in sickle cell disease: flow-cytometric measurement and clinical associations
Year: 1996
Type: article
Study design: Observational Study
Abstract: Increased exposure of phosphatidylserine (PS) in erythrocytes has been postulated to contribute to the pathophysiology of sickle cell disease because of its possible effects on blood coagulation, cell adhesion, and cell clearance. We developed a flow-cytometric assay to measure exposure of PS on the outer face of the erythrocyte membrane based on addition of fluorescein-annexin V to whole-blood specimens. The assay correlated linearly with binding of 125I-annexin V (r2 = .95, n = 125 samples). Normal donors (n = 30) showed virtually no annexin-positive cells (0.34% +/- 0.18% for 24-hour old samples). In contrast, annexin V binding was above the upper limit of normal in 96% of 205 specimens from 17 adult sickle cell and 2 beta-thalassemia patients; the mean percentage of annexin-positive cells was 2.86% +/- 2.00% (range, 0.4% to 12.0%). Values varied substantially over time for some patients, and mean values varied between patients. The percentage of annexin-positive cells always decreased after transfusion (11 events in 6 patients), and out of proportion to the amount of blood transfused. In conclusion, increased exposure of PS on a subpopulation of erythrocytes in vivo is a virtually universal feature of sickle cell disease, and its measurement may be useful to evaluate clinical status and response to therapeutic measures such as blood transfusion.
Source: Blood
Authors: BL Wood, DF Gibson, JF Tait
Institution: University of Washington
Language: English
Subfield: Genetics (clinical)
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
Award: SCOR IN ARTERIOSCLEROSIS
OpenAlex ID: W13114315
