Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Background: Pre-eclampsia (PE) is a common disorder of pregnancy that usually presents with hypertension and proteinuria. The clinical presentation arises from soluble factors released into the maternal circulation from the placenta owing to the stress of syncytiotrophoblast, consequence of defective placentation occurring in the first half of pregnancy. Reduced tolerance of the semiallogeneic fetus by the maternal immune system has been proposed as first trigger leading to poor placentation. We previously observed aberrant expression of human leukocyte antigen (HLA)-DR molecules in the syncytiotrophoblast of a subset of women with PE. Aim of this study was to investigate abnormal expression of circulating HLA-DR in syncytiotrophoblast-derived extracellular vesicles (STBEVs) in women with PE compared to normal pregnant women. Methods: peripheral venous blood was collected from 22 women with PE and 22 normal pregnant women. Circulating STBEVs were collected by ultra-centrifugation (120000 g) and analyzed for the expression of HLA-DR and placental alkaline phosphatase (PLAP), a specific marker of the placenta, by Western blot analysis and flow cytometry. Results: circulating STBEVs positive for HLA-DR were observed in 64% of PE women while no HLA-DR positivity was detected in any of the controls (P<0.01). Conclusions: Aberrant expression of HLA-DR in circulating STBEVs is specifically associated to PE. Further studies are required: a) to define the role of aberrant placental expression of HLA-DR molecules in the pathogenesis of PE; b) evaluate a possible application of detecting circulating HLA-DR positive STBEVs in the diagnosis and prediction of PE in the first and second trimester of pregnancy.

Original publication




Journal article


Front Immunol

Publication Date





human leukocyte antigen, placenta, pre-eclampsia, pregnancy, syncytiotrophoblast extracellular vesicles