Auto-antibodies against the angiotensin II type I receptor in women with uteroplacental acute atherosis and preeclampsia at delivery and several years postpartum

Background: Uteroplacental acute atherosis is a pregnancy-specific lesion resembling early stages of atherosclerosis found frequently in preeclampsia. Preeclampsia is associated with an increased risk for future maternal atherosclerotic cardiovascular disease. The renin-angiotensin-system plays a role both in atherosclerosis and in preeclampsia. Circulating agonistic autoantibodies at the angiotensin-II type 1 receptor (AT₁-AA) are increased in preeclampsia. We hypothesized an association between AT₁-AA at delivery and postpartum with acute atherosis in pregnancy.

Material and methods: Maternal serum and decidua basalis tissue was collected at elective cesarean section (n = 41; 24 preeclampsia, 17 normotensive controls). Circulating AT₁-AA were detected by a bioassay using spontaneously beating rat cardiomyocytes at delivery (n = 41) and 5-8 years postpartum in a subgroup (n = 10). Decidual acute atherosis was assessed by immunohistochemistry.

Results: Significantly less normotensive controls (18%; 3/17) than women with preeclampsia (58%; 14/24) were AT₁-AA positive at delivery, p<0.01. Uteroplacental acute atherosis and circulating AT₁-AA at delivery were not significantly correlated. Postpartum, 2 prior preeclamptic women had circulating AT₁-AA, both without acute atherosis in pregnancy.

Conclusions: Our results confirm that circulating AT₁-AA are present significantly more often in preeclampsia than in normotensive pregnancy, however without association to acute atherosis. Whether circulating maternal AT₁-AA or acute atherosis target young women at increased long-term cardiovascular risk warrants further investigations.