Decreased circulating levels of plasmacytoid dendritic cells in women with early-onset preeclampsia.

The role of plasmacytoid dendritic cells (pDCs), and myeloid dendritic cells (mDCs) in women with preeclampsia has not been elucidated. We compared the frequency of peripheral pDCs, mDCs, NK cells, and T helper 17 (Th17) cells among non-pregnant/pregnant women, and women with early-/late-onset preeclampsia. We examined pDCs and mDCs using Anti-Human Lineage Cocktail 3 (CD3, CD14, CD19, and CD20), HLA-DR, CD11c, and CD123. We detected NK cells using Lineage cocktail, CD8, CD16, and CD56. We determined Th17 cells using CD3, CD4, CD8, CXCR3, and CCR6. We recruited 13 non-pregnant women, 50 normal pregnant women, 13 women with early-onset preeclampsia (onset at <34 gestational weeks), and 10 women with late-onset preeclampsia. The fraction of pDCs in women with early-onset preeclampsia was significantly lower than in non-pregnant women and normal pregnant women at 19-29 gestational weeks (4.1 % vs. 41.2 % and 19.0 %, respectively [p = 0.0005, and p = 0.025]), however, the fraction of pDCs in late-onset preeclampsia was not significantly different from normal pregnant women at 37 gestational weeks (11.1 % vs. 29.1 %, respectively [p = 0.149]), although it was significantly lower than in non-pregnant women (11.1 % vs. 41.2 %, respectively [p = 0.044]). The fraction of Th17 cells in women with early-onset preeclampsia was significantly higher than in normal pregnant women at 19-29 gestational weeks (p = 0.022). In conclusion, the level of circulating pDCs was lower in early-onset preeclampsia than in non-pregnant and pregnant women, suggesting the role of pDCs in the pathogenesis of early-onset preeclampsia.