Endothelial cell are the cells forming the endothelium, i.e. the lining of blood vessels. They are regulators of the placental barrier and vascular tone and a site of gas and nutrient exchange between blood and tissue. For our research, we routinely isolate feto-placental endothelial cells from the placental chorionic plate. This method has already been published (Lang et al. 2008, doi: 10.1111/j.1432-0436.2008.00302.x.) and further refined (Leopold et al. 2018, doi:10.1007/s00418-019-01815-2). We isolate these cells not only from placentas of uncomplicated pregnancies, but also from those in which the pregnancy occurred due to pre-eclampsia or gestational diabetes. We use the cells to study cell metabolism, signaling pathways and cellular communication as well as placental angiogenesis (formation of new blood vessels), e.g. in 3D cell culture.