The endothelium plays an important role in inflammation with the ability to interact with cells of the immune system. Endothelial cells (ECs) represent a heterogeneous population of cells in term of secretion of inflammatory mediators, modulation of adhesion molecules, leakiness and pro-coagulant activity. No data are available for decidual ECs (DECs) which exert fundamental roles for the progression of pregnancy. The aim of our work was to compare microvascular ECs isolated from decidua (DECs) with ECs isolated from non-pregnant uterus (UtMECs) and adult skin (ADMECs), for the expression of adhesion molecules and cytokines before and after stimulation with pro-inflammatory molecules such as LPS, TNF-alfa, IFN-gamma and IL-1-beta. Furthermore we investigated the vascular permeability of DECs in response to permeabilizing stimuli such as PAF, histamine and bradikinine. Initially we analyzed the presence of about 30 cytokines, with luminex technology, in the endothelial cell supernatants after stimulation with pro-inflammatory stimuli. Our results showed that DECs are the unique ECs able to express IP-10 and MIG in response to IFN-gamma. DECs express low levels of IL-8, MCP-1, RANTES and IL-6 after stimulation with pro-inflammatory molecules and are unresponsive to LPS stimulation. The results of ELISA experiments on the whole cell showed that DECs constitutively express ICAM-1 and, after stimulation with pro-inflammatory molecules are unable to express VCAM-1 and only moderately up-regulate E-selectin and ICAM-1.The behavior of DECs in response to classical permeabilizing stimuli was studied using a transwell model system and FITC-conjugated BSA was used as an indicator of increased permeability. Our results showed that DECs are not responsible to vasoactive stimuli while UtMECs show a lower responsiveness compared to ADMECs. We conclude that decidual endothelium shows an anti-inflammatory behavior compared to microvascular endothelium obtained from other districts.
