Endothelial dysfunction in hypertension in pregnancy: associations between circulating endothelial cells, circulating progenitor cells and plasma von Willebrand factor.

BACKGROUND: Endothelial damage/dysfunction has been related to hypertension in pregnancy, with implications in pregnancy outcomes. We hypothesised abnormal levels of circulating endothelial cells (CECs), circulating progenitor cells (CPCs) and plasma von Willebrand factor (vWf, a marker of endothelial damage/dysfunction) in pregnant women with hypertension, when compared to pregnant normotensives and non pregnant healthy controls.
METHODS: Our study groups were 3rd trimester hypertensive pregnant women, 40 age matched normotensive pregnant women and 50 non pregnant healthy controls. CECs were measured by immunomagnetic separation using anti-CD146 monoclonal antibody coated beads. CPCs were defined using flow cytometry as CD133+/CD34+/CD45-. vWf was measured by ELISA.
RESULTS: Hypertensive pregnant women had significantly higher CECs compared to normotensive pregnant women and non pregnant healthy controls (p < 0.001). CPCs were raised in the normotensive pregnant group compared with hypertensive pregnant and non pregnant healthy controls (p < 0.05). Both pregnant women groups had significantly higher vWF than the non pregnant controls. CEC levels correlated with both systolic and diastolic BP (r = 0.28, p < 0.005 and r = 0.31, p < 0.001, respectively). vWf correlated with CECs (r = 0.39, p < 0.0001). Multiple linear regression analysis revealed hypertension in pregnancy as an independent predictor of CEC levels (p < 0.0001).
CONCLUSIONS: Hypertension in pregnancy is characterised by abnormalities in the vascular endothelium, with abnormal CECs and vWf that correlate with BPs. This may reflect dysfunctional processes that are counteracted with reparative attempts at restoring endothelial integrity.