29 Fibrinogen alters the expression of markers of inflammation, adhesion and angiogenesis by monocytes from women with pre-eclampsia in co-culture with vascular endothelial cells

Abstract

Objectives Pre-eclampsia (PE) is characterized by an exaggerated systemic inflammatory response and generalized endothelial dysfunction. Having recently demonstrated that fibrinogen, an endogenous ligand of TLR4, activates monocytes from women with pre-eclampsia (Al-ofi et al., 2014), we sought to determine whether fibrinogen alters the expression of markers of inflammation, cell adhesion and angiogenesis by monocytes from women with pre-eclampsia, in co-culture with human umbilical venous endothelial cells (HUVEC), in a manner similar to the exogenous TLR ligand LPS, compared to normotensive women. Methods HUVECs were isolated from umbilical cords, cultured, passaged and seeded onto gelatin-coated 12-well tissue culture plates until they reached 80–90% of confluence. Then monocytes, isolated from 9 PE (GA=33.6±3.0) and 9 normal pregnant (GA=31.6±3.8) women, were plated on top of HUVECs at the fractional rate of 1 monocyte to 5 HUVECs. Mono- and co-cultures were stimulated with LPS and fibrinogen. Flow cytometry was used to confirm monocytes and endothelial cells in the model. We determined the expression levels of inflammatory cytokines (IL-6 and IL-1 β ), chemokines (IL-8 and MCP-1), angiogenic (VEGF) and anti-angiogenic (sFLT-1) factors, as well as adhesion molecule (sVCAM-1) in supernatant medium by cytometric array. ELISA was used to measure sFLT-1. Results Fibrinogen induced greater amounts of IL-1 β and VCAM-1 from PE co-culture than from NP co- culture ( P P Conclusion Fibrinogen promotes monocyte-endothelial cell adhesion and angiogenesis but suppresses the expression of inflammatory markers in pre-eclampsia. Although the physiological implications of these intriguing observations are unclear our findings suggest that fibrinogen contributes to the regulation of cell adhesion, angiogenesis and inflammation by mechanisms not wholly dependent on TLR4 stimulation.