Upregulation of the CD40-CD40 ligand system in pre-eclampsia

Objective: To investigate the CD40-CD40 ligand (CD40L) system in women with pre-eclampsia. Methods: Expression of CD40 on monocytes and expression of CD40 and CD40L on platelets were determined by whole blood flow cytometry in 23 women with pre-eclampsia and in 23 normotensive pregnant women. Serum levels of soluble CD40L in both groups of women were measured by enzyme-linked immunosorbent assay. Results: There was a significantly higher expression of CD40 and CD40L on platelets and CD40 on monocytes in the women with pre-eclampsia compared with normotensive pregnant women (P < 0.001 for all comparisons). The serum concentration of soluble CD40L was significantly higher in women with pre-eclampsia compared with normotensive pregnant women (P = 0.012). Conclusion: Pre-eclampsia is associated with activation of the CD40-CD40L system. The activation of this system may contribute to the development or maintenance of the proinflammatory and prothrombotic responses, increased cytokine production, and endothelial cell dysfunction found in pre-eclampsia. (C) 2009 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.