Increased circulating interleukin-17 levels in preeclampsia

•We measured serum IL-17, sFlt-1, and PlGF level in normal pregnancy and preeclampsia.•Serum IL-17 levels were increased in women with preeclampsia.•Levels of IL-17 were not related to those of angiogenic factors in preeclampsia.•Elevated IL-17 level and sFlt-1/PlGF ratio had an additive effect on preeclampsia.

Increasing evidence suggests that an exaggerated maternal systemic inflammatory response and an angiogenic imbalance might play a central role in the pathogenesis of preeclampsia. We determined circulating levels of interleukin-17 (IL-17) along with those of angiogenic factors in healthy nonpregnant and pregnant women and preeclamptic patients, and examined whether serum IL-17 levels of preeclamptic patients were related to their clinical features and angiogenic factor concentrations. Fifty-nine preeclamptic patients, 60 healthy pregnant women and 56 healthy nonpregnant women were involved in this case-control study. Serum levels of IL-17A were measured using a high-sensitivity ELISA. Serum total soluble fms-like tyrosine kinase-1 (sFlt-1) and biologically active placental growth factor (PlGF) levels were determined by electrochemiluminescence immunoassay. For statistical analyses, nonparametric methods were applied. Serum IL-17 levels were significantly higher in preeclamptic patients than in healthy nonpregnant and pregnant women. We did not find any relationship between serum IL-17 concentrations of preeclamptic patients and their clinical features and serum sFlt-1 and PlGF levels or sFlt-1/PlGF ratios. However, elevated serum IL-17 level and sFlt-1/PlGF ratio were found to have an additive effect on the risk of preeclampsia, as shown by the substantially higher odds ratios of a combination of the two than of either alone. In conclusion, serum IL-17 levels are increased in preeclampsia, which may contribute to the development of the excessive systemic inflammatory response characteristic of the maternal syndrome of the disease. In addition, elevated serum IL-17 level and sFlt-1/PlGF ratio had an additive (joint) effect on the risk of preeclampsia.