Comprehensive Maternal Serum Proteomic Profiles of Preclinical and Clinical Preeclampsia Juha Rasanen,*,†,‡ Anna Girsen,‡ Xinfang Lu,§ Jodi A. Lapidus,†,§ Melissa Standley,§ Ashok Reddy,§ Surendra Dasari,§ Archana Thomas,§ Thomas Jacob,§ Anneli Pouta,‡,| Helja-Marja Surcel,| Jorge E. Tolosa,† Michael G. Gravett,⊥ and Srinivasa R. Nagalla†,§ Departments of Obstetrics and Gynecology, Pediatrics, Public Health and Preventive Medicine, Oregon Health & Science University, Portland, Oregon 97239, Department of Obstetrics and Gynecology, Oulu University Hospital, Oulu, Finland, Proteogenix, Inc., Beaverton, Oregon 97006, National Institute for Health and Welfare, Oulu, Finland, and Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington 98195 Received March 4, 2010
Abstract: We systematically characterized maternal serum proteome in women with clinical preeclampsia (PE) and asymptomatic women in early pregnancy that subsequently developed PE. Clinical PE cohort comprised 30 patients with mild PE, 30 with severe PE, and 58 normotensive women. Preclinical PE cohort included 149 women whose serum samples were collected at 8-14 gestational weeks and in whom 30 women later developed mild and 40 severe PE. Serum proteome was analyzed and enzymelinked immunosorbent assays were used for protein quantification. In Clinical PE, fibronectin, pappalysin-2, choriogonadotropin-β, apolipoprotein C-III, cystatin-C, vascular endothelial growth factor receptor-1, and endoglin were more abundant compared to normotensive women. In preclinical PE, differently expressed proteins included placental, vascular, transport, matrix, and acute phase proteins. Angiogenic and antiangiogenic proteins were not significant. We conclude that placental and antiangiogenic proteins are abundant in clinical PE. In preclinical PE, proteomic profile is distinct and different from that in clinical PE. Keywords: Fetus • Hypertensive Disorders • Pregnancy • Proteome
Introduction Preeclampsia (PE) complicates 5-6% of pregnancies and is associated with substantial maternal and neonatal mortality and morbidity.1 Its etiology is still unclear. However, there are multiple risk factors associated with PE.2,3 According to current understanding, PE precedes in two stages.4 In the first stage, trophoblastic invasion early in pregnancy, regulated by local oxygen tension and immune-mediated interactions, is thought * To whom correspondence should be addressed. Juha Rasanen, MD, Department of Obstetrics and Gynecology, Oregon Health Sciences University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239. Tel: 503-4942101. Fax: 503-494-5296. E-mail:
[email protected]. † Oregon Health & Science University. ‡ Oulu University Hospital. § Proteogenix, Inc. | National Institute for Health and Welfare. ⊥ University of Washington.
4274 Journal of Proteome Research 2010, 9, 4274–4281 Published on Web 06/23/2010
to be inadequate and fails to remodel spiral arteries leading to reduced placental perfusion. In the second stage, clinical manifestations of PE become apparent. Multiple circulating angiogenic and antiangiogenic peptides have been associated with PE. These include soluble fms-like tyrosine kinase 1 (sFlt-1), an antiangiogenic protein that is increased in the placenta and serum of women with PE,5,6 and low serum concentrations of angiogenic proteins, including placental growth factor (PlGF) and vascular endothelial growth factor (VEGF).6,7 Levine and colleagues demonstrated an increase in circulating sFlt-1 concentrations beginning 5 weeks before the onset of clinical PE, accompanied by decreases in the circulating free PlGF and VEGF levels.6 First trimester serum PlGF concentrations have been shown to be lower in women who subsequently developed PE.8 Furthermore, in women with subsequent PE, first trimester sFlt-1 levels were lower and second trimester concentrations higher than those of women with uncomplicated pregnancies.9 Whether these abnormalities in circulating angiogenic proteins reflect primary or secondary pathophysiologic events in PE remains unclear. Recent advances in proteomic methods of protein separation, identification, and quantitation enable comprehensive evaluations of low- and high-abundance proteins in various biological fluids.10-13 In the present study, we hypothesized that a systematic analysis of the maternal serum proteome profile could identify protein biomarkers that are differentially expressed in patients with PE. Specifically, we sought to evaluate whether (1) the maternal serum proteomic profile for patients with clinical PE differs from those with normotensive pregnancies, (2) there is a difference in the proteomic profiles of mild and severe PE patients, and (3) there is an early pregnancy maternal serum proteomic profile that can identify patients destined to develop clinical PE.
Materials and Methods A total of 267 women were included in this study of two distinct patient populations. The first group, referred to as the Clinical PE cohort, included 118 women who were recruited in the Department of Obstetrics and Gynecology, Oulu University Hospital, Oulu, Finland between years 2004 and 2006. Fifty-eight of these patients were normotensive, and 30 subjects each had mild or severe PE, as defined by the Working Group 10.1021/pr100198m
2010 American Chemical Society
technical notes
Proteomic Profiles of Preclinical and Clinical Preeclampsia
Table 1. Demographic and Clinical Characteristics of the Study Groups (Preclinical PE n ) 149; Clinical PE n ) 118)a Preclinical PE
Maternal age (year) GA at sample collection (week) GA at Delivery (week) GA at PE start (week) Birth Weight (g) Nulliparity (%) Smoker (%) Delivery
