Human decidualized endometrial T lymphocytes do not substantially down-regulate CD3zeta.
OBJECTIVE
The T-cell antigen receptor (TCR) has been reported to be down-regulated on T-cells in the decidualized endometrium in early pregnancy.


METHODS
The expression of CD3zeta, a component of the TCR complex, has been investigated in human first-trimester decidual T-cells using flow cytometric analysis of permeabilized cells.


RESULTS
Levels of CD3zeta expression were significantly lower in decidual than in peripheral T-cells from non-pregnant women, as assessed by mean fluorescence intensity (4.2 vs. 5.5, logarithmic scale, P < 0.05). However, when decidual and peripheral T-cells from the same subjects were analyzed (n = 10), mean levels of CD3zeta were slightly, but not significantly, lower in decidual than in peripheral T-cells (P > 0.1). CD3zeta was not substantially down-regulated systemically as mean cytoplasmic CD3zeta levels did not differ significantly between peripheral blood T-cells from pregnant women and non-pregnant controls (P > 0.2). CD8+ cells outnumber CD4+ cells in decidua, but neither the proportions of these two T-cell subsets positive for cytoplasmic CD3zeta nor the mean levels of CD3zeta were significantly different.


CONCLUSIONS
These results indicate that human decidual T-cells do not greatly down-regulate CD3zeta, but it is unclear if a small decrease in mean levels may be sufficient to compromise their capacity for activation.
Bedenicki
I
I
Department of Immunology, University of Liverpool, UK.
Newton
D J
DJ
Flanagan
B F
BF
Johnson
P M
PM
Rukavina
D
D
Christmas
S E
SE
D017252:CD3 Complex / Q000378:metabolism*; D003656:Decidua / Q000276:immunology*; D015536:Down-Regulation; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D017252:CD3 Complex; D011948:Receptors, Antigen, T-Cell