These findings add support to the novel concept that preeclampsia is an autoimmune disease associated with AT1-AA

These findings add support to the novel concept that preeclampsia is an autoimmune disease associated with AT1-AA.13We believe these initial clinical studies coupled with our bioassay have provided a strong foundation for us to perform a large scale clinical studies in the future. == METHODS == == Materials == Tissue culture medium (RPMI 1640), fetal bovine serum (FBS), and antibiotics such as penicillin-streptomycin (100), and geneticin (G418, 50 mg/ml) were purchased from Invitrogen Life Technologies (Carlsbad, CA). to the severity of the disease. Intriguingly, among severe preeclamptic patients, we discovered that the titer of AT1-AA is usually significantly correlated with the clinical features of preeclampsia: systolic blood pressure (r=0.56), proteinuria (r=0.70) and sFlt-1 level (r=0.71), respectively. Notably, only AT1-AA Rabbit polyclonal to AMDHD1 but not sFlt-1 levels are elevated in GH patients. These data serve as compelling clinical evidence that AT1-AA is usually highly prevalent in preeclampsia Ecdysone and its titer is usually Ecdysone strongly correlated to the severity of the disease. Keywords:preeclampsia, gestational hypertension, angiotensin receptor autoantibodies, sFlt-1, proteinuria == INTRODUCTION == Preeclampsia is usually a serious hypertensive disorder of pregnancy that affects approximately 5% of pregnancies and remains a leading cause of maternal and neonatal mortality and morbidity in the United States and the world.13The disease is multifactorial and includes such clinical features Ecdysone as high blood pressure, proteinuria, inflammation, endothelial dysfunction, vasoconstriction and placental abnormalities.47The clinical symptoms in the advanced stages of preeclampsia, include cerebral hemorrhage, renal failure and the HELLP syndrome. In serious cases termination of pregnancy is the only available option to prevent further deterioration of the fetus and mother. Despite being a leading cause of maternal death and a major contributor to maternal and perinatal morbidity, the triggering factors and underlying mechanisms responsible for the pathogenesis of preeclampsia remain elusive. Numerous studies have shown that women with preeclampsia possess angiotensin receptor agonistic autoantibodies (AT1-AAs) that bind to and activate Ecdysone the AT1angiotensin receptor in multiple cellular systems and provoke biological responses that are relevant to the pathophysiology of preeclampsia.813For example, AT1-AAs increase the contraction rate of rat cardiomyocytes, elevate levels of the anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1) leading to decreased angiogenesis in endothelial cells, increased plasminogen activator inhibitor-1 (PAI-1) production resulting in decreased trophoblast invasion and increased NADPH oxidase production in trophoblast cells resulting in oxidative stress.1417However, these studies were restricted to the use ofin vitrocultured cell systems and therefore did not directly address the relevance of AT1-AAs to hypertension and proteinuria, the defining features of preeclampsia. However, recent experiments have demonstrated that this injection of pregnant mice with AT1-AAs recapitulates the key features of preeclampsia, including hypertension, proteinuria, renal and placental morphologic changes and an increase in the concentration of anti-angiogenic factor sFlt-1.18Thus, thesein vivostudies provide the first direct Ecdysone evidence for a pathophysiological role of AT1-AA in preeclampsia and suggest that these autoantibodies contribute to the pathogenesis of preeclampsia. However, the prevalence of AT1-AA in preeclampsia remains unknown and the correlation of AT1-AA to the severity of the disease remains undetermined due to the lack of a sensitive and convenient assay to accurately measure AT1-AA in human sera. In this study, because of our newly developed sensitive and high throughput luciferase bioassay, we were able to address two important clinical questions: 1) What percentage of women with preeclampsia contain AT1-AA, and, 2) Does the titer of AT1-AA correlate to the severity of disease? Using this bioassay, we have provided the first compelling patient evidence that AT1-AA is usually highly prevalent in preeclampsia and its titer strongly correlates to the severity of the disease. These findings add support to the novel concept that preeclampsia is an autoimmune disease associated with AT1-AA.13We believe these initial clinical studies coupled with our bioassay have provided a strong foundation for us to perform a large scale clinical studies in the future. == METHODS == == Materials == Tissue culture medium (RPMI 1640), fetal bovine serum (FBS), and antibiotics such as penicillin-streptomycin (100), and geneticin (G418, 50 mg/ml) were purchased from Invitrogen Life Technologies (Carlsbad, CA). Human Angiotensin II was obtained from Sigma (St. Louis, MO). Losartan (COZAAR) was a gift from Merck Research Laboratory (Rahway, NJ). The seven amino acid peptide (7aaAFHYESQ), is an epitope sequence present on the second extracellular loop of the AT1receptor that is recognized by AT1-AA. These peptides were synthesized by the Protein Chemistry Core Laboratory, Baylor College of Medicine (Houston, TX). Protein G Sepharose 4 Fast Flow, used for IgG isolation was purchased from Amersham Pharmacia Biotech (Piscataway, NJ). PathDetect NFATcis-Reporting system and syntheticRenillaluciferase reporter vector were purchased from Stratagene (La Jolla, CA) and PromegaCorp. (Madison, WI) respectively. == Patients == Patients who were admitted to Memorial Hermann Hospital were identified by the obstetrics faculty of the University of Texas Medical School at Houston. Twenty seven patients were diagnosed with severe preeclampsia based on the definition set by the National High Blood Pressure Education Program Working Group report.19The criteria include the presence of high blood pressure of 160/110 mmHg and urinary protein of 300 mg in a 24 hr period or a.