Agonistic antibodies directed at the angiotensin II, AT1 receptor in preeclampsia

Immune mechanisms and circulatimg mediators may be important in the pathogenesis of preeclampsia. We review our findings on agonistic antibodies against the angotensin II (Ang II) receptor (AT1-AA) and their possible role in file pathogenesis of this disorder. AT1-AA appear in the course of precclampsia and are largely gone by 6 weeks after delivery. AT1-AA detection relies on a bioassay using spontaneously beating neonatal rat cardiomyocytes. Their specificity has been documented by other methods, including Western blotting co-localization, and co-localization and co-immunoprecipitation experiments. AT1-AA induce signaling in vascular cells and trophoblasts including transcription factor activation. The signaling results in tissue factor production and reactive oxygen species generation, both of which have beem implicated in preeclampsia. The role of AT1-AA in precclampsia and other severe hypermisive conditions has not yet been proved with certainty. However, we believe the findings are compelling and warrant further study. (J Soc Gynecol Investig 2006; 13:79-86) Copyright (c) 2006 by the Society for Gynecolgic Investigation.