Proteomic profiling of maternal plasma collected longitudinally during pregnancy by surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF MS)

Abstract

DURING PREGNANCY BY SURFACE ENHANCED LASER DESORPTION IONIZATION TIME OF FLIGHT MASS SPECTROMETRY (SELDI-TOF MS) DANIELLE IPPOLITO, MIKE HARTENSTINE, HEIDI CEDERHOLM, ASPEN BERGMANN, PETER NAPOLITANO, JEREMY CELVER, PATRICK MCNUTT, Madigan Army Medical Center, Department of Clinical Investigation, Tacoma, Washington, Madigan Army Medical Center, Tacoma, Washington OBJECTIVE: Maternal plasma is an accessible biological fluid for investigating proteins modulated during fetal development and maintenance of pregnancy. Here we present demographics and pilot data from our ongoing ‘‘Plasma Pregnancy Proteome’’ study to identify (a) preclinical biomarkers for adverse outcomes such as PROM and preeclampsia and (b) proteins reflecting changes in fetal and maternal physiology during development. STUDY DESIGN: Plasma is collected prospectively from 300 primagravid pregnancies at five time points for a longitudinal proteomic comparison during normal and complicated pregnancies. Unfractionated plasma from 7 patients at post-conception weeks 4-10, 10-12, 16-22, 26-28 and 36-38 was profiled by SELDI-TOF MS using (1) hydrophobic (H50), (2) strong anion exchange (Q10) and (3) copper-binding (IMAC) chromatographic surfaces. RESULTS: To date, we have enrolled 100 women from ethnically diverse backgrounds, including representative instances of preterm labor, preeclampsia, first and second trimester miscarriage and chorioamnionitis. In the pilot study we used SELDI-TOF MS to identify 127, 18 and 64 unique protein peaks on the H50, Q10 and IMAC surfaces, respectively, which were present in plasma from all women. Of these, 54, 18 and 40 proteins were modulated significantly (p!0.05) as a function of gestational age. In particular, one protein (w8250Da) increased O5-fold (R2=0.96, figure) on all surfaces examined. We are currently targeting a subset of proteins for identification and validation.