Placental fractalkine immunoreactivity in preeclampsia and its correlation with histopathological changes in the placenta and adverse pregnancy outcomes*

Abstract

Introduction: Preeclampsia is a systemic inflammatory disorder and a major cause of maternal and fetal mortality. Fractalkine (CX3CL1) is a member of the chemokine family with multiple functions in the organization of the immune system. It is up-regulated in inflammatory disorders. During inflammation, fractalkine enhances tissue destruction and inflammatory cell invasion. We aimed to investigate the alteration of fractalkine in the placental tissues of pregnant women with preeclampsia and the correlation of this alteration with clinicopathological variables. Materials and methods: Alteration of fractalkine in placental tissue specimens was determined immunohistochemically in 84 pregnant women: 33 women with mild preeclampsia, 19 women with severe preeclampsia, and 30 women with normal pregnancy. Preeclampsia was diagnosed using current guidelines of the American College of Obstetricians and Gynecologists. Results: Pregnant women with mild and severe preeclampsia revealed significantly higher fractalkine expression in syncytiotrophoblast cells than in the normotensive group (p = .0051 and .0001, respectively). The expression of fractalkine in preeclampsia was positively correlated with clinical parameters including the presence of intrauterine growth restriction, systolic and diastolic blood pressure, and 24-h urine protein, whereas it was negatively correlated with plasma albumin levels and placental weight. Additionally, the pathological changes in the placenta-including the presence of syncytiotrophoblast basement membrane thickening, increased number of syncytial knots, and vascularization of terminal villi were significantly correlated with fractalkine expression in pregnant women with preeclampsia. Conclusions: Overexpression of fractalkine in pregnant women with preeclampsia, as well as the correlation between fractalkine expression and poor pregnancy outcomes and placental histopathological changes may be associated with the underlying mechanisms of preeclampsia.