Differential expression of TcR-CD3 zeta as evidence for altered immunoregulation in preeclamptic versus normotensive women
ABSTRACT The study was undertaken to exhibit and quantify the difference in modulation of CD3-zeta protein (an integral component of the T-cell receptor) in preeclamptic and normotensive women.
Serum was collected from 10 preeclamptic and 10 normotensive women at >or=37 weeks' gestation on admission. Jurkat E-61 cells were incubated with the sera (20% volume to volume) and analyzed with Western immunoblot using mouse monoclonal CD3-zeta antibody. Enhanced chemiluminescence and densitometry were used to qualitatively measure zeta expression of the cells. A de novo flow cytometry assay was developed to quantify the difference in CD3-zeta expression of these cells. Comparisons were performed by t test (P<.05 was significant).
Preeclamptic patient sera produced a 2.4-fold increase in CD3-zeta expression than normotensive patients on Western blot (P<.01). Flow cytometry showed that preeclamptic sera had a 1.4-fold higher expression of CD3-zeta compared with normotensive patients (P<.0003).
TcR/CD3-zeta expression is normally suppressed in pregnancy. Loss of this suppression occurs in preeclamptic patients, implying increased T-cell function.
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