Search for an Association between V249I and T280M CX3CR1 Genetic Polymorphisms, Endothelial Injury and Preeclampsia: The ECLAXIR Study

BACKGROUND Preeclampsia and coronary-artery disease share risk factors, suggesting common pathophysiological mechanisms. CX3CR1/CX3CL1 mediates leukocyte migration and adhesion and has been implicated in the pathophysiology of several inflammatory diseases. M280/I249 variants of CX3CR1 are associated with an atheroprotective effect and reduced endothelial dysfunction. The aim of this study was to search for an association between V249I and T280M polymorphisms of CX3CR1, preeclampsia and endothelial dysfunction. METHODOLOGY/PRINCIPAL FINDINGS We explored these polymorphisms with real-time polymerase chain reaction in a case-control study (184 white women with preeclampsia and 184 matched normotensive pregnant women). Endothelial dysfunction biomarkers including von Willebrand factor, VCAM-1 and thrombomodulin, as well as the soluble form of CX3CL1 were measured by enzyme-linked immunosorbent assays (ELISA). The I249 and M280 alleles were associated neither with preeclampsia, nor with its more severe form or with endothelial injury. In contrast, we found a trend toward increased CX3CL1 levels in preeclampsia patients, especially in early-onset- preeclampsia as compared to its level in later-onset- preeclampsia. CONCLUSIONS/SIGNIFICANCE This is the first study to characterize the CX3CR1 gene polymorphisms in patients with preeclampsia. We found no differences in genotype or haplotype frequencies between patients with PE and normal pregnancies, suggesting that maternal CX3CR1 V249I and T280M polymorphisms do not increase susceptibility to preeclampsia. Further studies should be performed to directly evaluate the pathophysiological role of CX3CL1, a molecule abundantly expressed in endometrium, which has been shown to stimulate human trophoblast migration.