Specific Features of TLR4 Expression in Structural Elements of Placenta in Patients with Preeclampsia

We studied the expression of TLR4 (Toll-like receptor 4) in the syncytiotrophoblast and vascular endothelial cells of terminal and stem placental villi in severe preeclampsia and normal pregnancy. In women of both groups, the expression of TLR4 was higher in the syncytiotrophoblast that in placental endothelial cells. In patients with severe preeclampsia, TLR4 expression in endothelial cells of terminal villi was 1.3-fold lower than in normal pregnancy. Lower TLR4 expression in the terminal villi endothelium in preeclampsia can underlie impaired recognition of damaging molecules with subsequent development of endothelial dysfunction and changes in immunological tolerance.