82-OR

Abstract

Objectives Urine is commonly used in clinical diagnostics, including during pregnancy and is a rich source of proteins; urine thus represents an attractive target for the development of predictive and diagnostic tests for pre-eclampsia. Methods We examined the urinary proteome from nulliparous women at 15 and 20 weeks gestation who subsequently developed pre-eclampsia as compared to those whose pregnancies were subsequently uncomplicated (samples were obtained through the SCOPE consortium). Urine samples were subjected to ultracentrifugation over a nominal molecular weight cut-off membrane of 10 kDa to increase sample concentration, and loadings were normalized to 100 ug/channel based upon sample concentration following Bradford assay. Proteins were subjected to iTRAQ derivatization according to standard protocols. Samples were analyzed using LC-MS/MS, upon a quadrupole time of flight mass spectrometer (QSTAR, ABSciex), equipped with a nanoflow HPLC (Eksigent). Data were analyzed using Mascot (Matrix Sciences) and Scaffold Q+ (Proteome Science). Results Patient samples were compared to a ‘master mix’ of pooled samples from normal pregnancies. Approximately 400 proteins could be identified from urine samples from patients at a FDR cut-off of 1%, with approximately 150 of these provided sufficient reporter ion data for quantification. Of these, a number of proteins were observed to be altered in expression in samples from women who subsequently developed pre-eclampsia, including periplakin 1, growth and differentiation factor 15 and ICOS ligand 1 (Figure). Conclusions iTRAQ labelling with LC-MS/MS analysis affords a method for low-to-medium throughput, quantitative analysis of urine protein content and concomitant identification of proteins. This proof-of-concept study suggests potential application for the prediction of pre-eclampsia. Disclosures S. Hart: None. L. Kenny: Shareholder Metabolomic Diagnostics. J. Myers: None. P. Baker: Shareholder Metabolomic Diagnostics.