Uterine microvascular endothelial cells (UtMVECs) and human umbilical vein endothelial cells (HUVECs) were obtained from Lonza and utilized before 28 HA ET AL. passage 7. These cells were cultured in the basal media supplied by the company, supplemented with the recommended kit of media additives (EGM2 SingleQuots-hydrocortisone, human epidermal growth factor [hEGF], FBS, VEGF, human fibroblast growth factor beta [hFGFb], E3R-insulin-like growth factor 1 [R3-IGF], ascorbic acid, heparin, and gentamicin/amphotericin-B). Human dermal microvascular endothelial cells (HDMECs; Promocell) were cultured on gelatin-coated dishes in endothelial cell growth medium MV (Promocell) supplemented with 5% fetal calf serum. HDMECs were used at passage 3 or 4.