Dysregulation of circulating autoantibodies against VEGF-A, VEGFR-1 and PlGF in preeclampsia - A role in placental and vascular health?

OBJECTIVES: Preeclampsia is a state of antiangiogenesis, with high levels of maternal circulating sVEGFR-1 (soluble vascular endothelial growth factor receptor 1, also named sFlt1) and low levels of PlGF (placenta growth factor). Various autoantibodies have been detected in preeclamptic patients. We hypothesize that circulating autoantibodies against VEGF-A (AA-VEGF-A), VEGFR-1 (AA-VEGFR-1) and PlGF (AA-PlGF) are present in preeclamptic women, with different levels from pregnant women with normotensive pregnancies. Secondly, we wanted to analyze if autoantibody levels are associated to sFlt1 or PLGF levels.

STUDY DESIGN: Retrospective cross sectional study of 88 women with singleton pregnancies who delivered at Oslo University Hospital of whom 46 had preeclampsia and 42 had uncomplicated normotensive pregnancies. Novel immunoassays for IgG-autoantibodies against VEGFA, VEGFR-1 and PlGF were developed and serum samples were assayed.

MAIN OUTCOME MEASURES AND RESULTS: AA-VEGF-A, AA-VEGF-R1 and AA-PlGF were significantly lower in preeclamptic pregnancies (n=42) compared to normotensive pregnancies (n=46) (p<0.05). On unadjusted analysis, only AA-VEGFA and AA-VEGFR-1 were predictors of PE, but none were independent predictors after adjusting for BMI (body mass index) and parity. In the subgroup of normotensive and PE women with overlapping sVEGFR-1/PlGF-ratios, AA-VEGF was a significant predictor of PE with AUC: 0.735.

CONCLUSION: IgG autoantibodies against VEGF-A VEGFR-1 and PlGF can be found in pregnant women. They are dysregulated in preeclampsia. The roles of these autoantibodies are unknown, but this study suggests they play a protective role in pregnancy. The levels of AA against VEGF-A, VEGFR-1 and PlGF might be important factors contributing to anti-angiogenesis regulation.