Angiotensin Receptor Agonistic Autoantibody Is Highly Prevalent in Preeclampsia

Abstract
Preeclampsia (PE), a syndrome affecting 5% of pregnancies, characterized by hypertension and proteinuria, is a leading cause of maternal and fetal morbidity and mortality. The condition is often accompanied by the presence of a circulating maternal autoantibody, the angiotensin II type I receptor agonistic autoantibody (AT1-AA). However, the prevalence of AT1-AA in PE remains unknown, and the correlation of AT1-AA titers with the severity of the disease remains undetermined. We used a sensitive and high-throughput luciferase bioassay to detect AT1-AA levels in the serum of 30 normal, 37 preeclamptic (10 mild and 27 severe), and 23 gestational hypertensive individuals. Here we report that AT1-AA is highly prevalent in PE (≈95%). Next, by comparing the levels of AT1-AA among women with mild and severe PE, we found that the titer of AT1-AA is proportional to the severity of the disease. Intriguingly, among severe preeclamptic patients, we discovered that the titer of AT1-AA is significantly correlated with t...