Influence of inflammatory infiltrate and alterations of the blood flow in the etiopathogenesis of the basement membrane of the amniotic epithelium (BMAE) thickening in patients with hypertensive syndromes in pregnancy

The histology and histomorphometry of umbilical cord cross section in preeclampsia and normal pregnancies: a comparative study

The umbilical cord is the connecting link between the mother and the fetus and its morphology is an indicator of fetal well-being. Preeclampsia is a disorder of pregnancy associated with new-onset hypertension, which occurs most often after 20 weeks of gestation. There are structural differences in the umbilical cord of normotensive and hypertensive pregnant women. This research aimed to study the histology and histomorphometry of umbilical cord areas in preeclampsia and compare the parameters with normal uncomplicated pregnancies of gestational age 37-40 weeks. A total of 70 umbilical cords were studied from preeclampsia (n = 35) and normal (n = 35) pregnancies. The parameters studied included cross-sectional areas (CSA) of umbilical cord, umbilical vein lumen, umbilical vein wall, umbilical artery lumen, umbilical artery wall, and Wharton's jelly, including the presence of edema in the vessel walls and Wharton's jelly and basement membrane thickening. The mean umbilical cord CSA was significantly higher in preeclampsia (p = 0.014). The mean umbilical artery lumen CSA was significantly lower than the normal pregnancy cords (p = 0.006). The mean Wharton's jelly CSA in preeclampsia was significantly higher than the normal pregnancy cords (p = 0.004). The parameters for umbilical vein lumen CSA, umbilical vein wall CSA, and umbilical artery wall CSA did not show any significant difference. Histological findings were edema (p < 0.001) and thickened basement membranes (p < 0.0001) were considered significant.

Amniotic mesenchymal cells from pre-eclamptic placentae maintain immunomodulatory features as healthy controls

Pre‐eclampsia (PE) is one of the most severe syndromes in human pregnancy, and the underlying mechanisms of PE have yet to be determined. Pre‐eclampsia is characterized by the alteration of the immune system's activation status, an increase in inflammatory Th1/Th17/APC cells, and a decrease in Th2/Treg subsets/cytokines. Moreover, inflammatory infiltrates have been detected in the amniotic membranes of pre‐eclamptic placentae, and to this date limited data are available regarding the role of amniotic membrane cells in PE. Interestingly, we and others have previously shown that human amniotic mesenchymal stromal cells (hAMSC) possess anti‐inflammatory properties towards almost all immune cells described to be altered in PE. In this study we investigated whether the immunomodulatory properties of hAMSC were altered in PE. We performed a comprehensive study of cell phenotype and investigated the in vitro immunomodulatory properties of hAMSC isolated from pre‐eclamptic pregnancies (PE‐hAMSC), comparing them to hAMSC from normal pregnancies (N‐hAMSC). We demonstrate that PE‐hAMSC inhibit CD4/CD8 T‐cell proliferation, suppress Th1/Th2/Th17 polarization, induce Treg and block dendritic cells and M1 differentiation switching them to M2 cells. Notably, PE‐hAMSC generated a more prominent induction of Treg and higher suppression of interferon‐γ when compared to N‐hAMSC, and this was associated with higher transforming growth factor‐β1 secretion and PD‐L2/PD‐L1 expression in PE‐hAMSC. In conclusion, for the first time we demonstrate that there is no intrinsic impairment of the immunomodulatory features of PE‐hAMSC. Our results suggest that amniotic mesenchymal stromal cells do not contribute to the disease, but conversely, could participate in offsetting the inflammatory environment which characterizes PE.