Changes in the subsets of dendritic cells and T cells in peripheral blood of patients with preeclampsia

Objective: To investigate the immunoregulation in pathogenesis of pregnancy induced hypertension (PIH) by observing the changes in the subsets of dendritic cells (DC) and T cells in the peripheral blood of patients with preeclampsia.

Methods: The study included 32 preeclampsia patients, 20 normal pregnancy subjects and 20 non-pregnant healthy controls. We harvested their peripheral blood cells and counted the percentages of myeloid DC (mDC) and plasmacytoid DC (pDC) in whole blood cells, and the numbers of CD4(+); IFN-γ(+);T (Th1), CD4(+); IL-4(+);T (Th2) and CD4(+); IL-17(+);T (Th17) subsets in peripheral blood mononuclear cells by flow cytometry, and worked out the ratio of Th1 to Th2.

Results: The percentage of mDC (0.33±0.12)% and the ratio of mDC/pDC (2.96±1.65) in preeclampsia patients were significantly higher than those in normal pregnancy subjects (P<0.05). The percentage of pDC (0.16±0.13)% was lower than that in normal pregnancy subjects (0.21±0.12)% (P<0.05). The percentages of IFN-γ, IL-4 and IL-17 in preeclampsia patients were (18.67±1.96)%, (1.88±0.51)% and (1.36±0.59)%, respectively, all with statistically significant difference from those of normal late pregnancy (P<0.01). In preeclampsia patients, mDC/pDC ratio was significantly positively correlated with Th1/Th2 (r=0.637, P<0.01) and the percentage of Th17 cells was negatively correlated with pDC cells and positively correlated with mDC/pDC (r=-0.670, 0.772, respectively; P<0.01).

Conclusions: Preeclampsia patients suffered the changes in dendritic cell subsets and abnormal expressions of Th1, Th2 and Th17, which might be an important reason for immune imbalance in preeclampsia patients.