Placental tissue acquisition
The placenta tissues were obtained at Maternity and Child Health Hospital of Pudong New District, Shanghai. Collections of tissues were performed with the approval of Ethics Committee of Medical Research of Maternity and Child Health Hospital of Pudong New District. Informed consent was obtained from all patients.
There were 43 pregnant women with normotension at term (37-40weeks) and 43 women with PE (36-40 weeks) included in the present study. Human subject data were summarized and indicated in Tab. S1. PE was defined as pregnancy-induced hypertension (blood pressure ≥140/90 mmHg) and proteinuria (≥0.3 g/24 h or ≥1 + according to a routine urinalysis) in women who were normotensive before pregnancy and had no other underlying clinical problems such as renal disease. Pregnant women with multiple pregnancies, intrahepatic cholestasis of pregnancy and those with type 1, type 2 or gestational diabetes mellitus, a history of kidney disease, or autoimmune disease were excluded. All of the placentas were collected within 1 hour of cesarean birth, and six small pieces of tissues from separate lobules were randomly taken in each placenta. The tissues were washed with cold saline, immediately frozen in liquid nitrogen and then stored at -80℃.