The expression of B7-H1 and B7-H4 co-stimulatory molecules on myeloid and plasmacytoid dendritic cells in pre-eclampsia and normal pregnancy

The aim of our study was to estimate the expression of B7-H1 and B7-H4 molecules on myeloid and plasmacytoid dendritic cells (DCs) in the peripheral blood of patients with pre-eclampsia, normal pregnant women and healthy non-pregnant women. Thirty-three patients with pre-eclampsia, 26 normal pregnant women, and 12 healthy non-pregnant women were included in the study. Dendritic cells were isolated from peripheral blood, stained with monoclonal antibodies against blood dendritic cell antigens and B7-H1 and B7-H4 molecules and estimated using flow cytometry. The expression of B7-H1 and B7-H4 molecules was significantly higher on CD1c+ myeloid and CD303+ plasmacytoid DCs in the first trimester of pregnancy than in the luteal phase of the ovarian cycle (CD1c+B7-H1+: 19.19 ± 10.55% vs. 11.99 ± 6.79%; p < 0.05; CD1c+B7-H4+: 12.01 ± 9.15% vs. 3.98 ± 1.97%, p < 0.001; CD303+B7-H1+: 4.15 ± 2.38% vs. 1.70 ± 0.87%, p < 0.05; CD303+B7-H4+: 5.44 ± 2.93% vs. 2.33 ± 1.54%, p < 0.01). Moreover, the expression of the B7-H1 molecule on CD1c+ DCs in the second trimester of normal pregnancy was significantly higher than in the first trimester, but in the third trimester they decreased compared with the second trimester (II vs. I trimester: 32.23 ± 11.30% vs. 19.19 ± 10.55%, p < 0.01; III vs. II trimester: 32.23 ± 11.30% vs. 22.39 ± 8.19%, p < 0.01). The expression of B7-H1 molecule on CD1c+ myeloid and CD303+ plasmacytoid DCs was significantly lower in pre-eclampsia than in healthy third-trimester pregnant women (CD1c+B7-H1+: 13.78 ± 6.26% vs. 22.39 ± 8.19%, p < 0.05; CD303+B7-H1+: 3.66 ± 2.46% vs. 8.65 ± 3.15%, p < 0.01). Higher expressions of B7-H1 and B7-H4 molecules on CD1c+ myeloid and CD303+ plasmacytoid DCs in the first trimester of pregnancy suggest the role they play in the immunomodulation during early pregnancy.