Biomarkers for diagnosis and prognosis of heart failure using label free LC-MSE

In the UK 900,000 people suffer from heart failure, of which 30-40% die within 1 year of diagnosis. Heart failure is a prevalent disease worldwide and is associated with high rates of morbidity and mortality. Current biomarkers suffer from poor levels of accuracy and efficacy. Therefore, accurate, reproducible, and reliable diagnostic and prognostic biomarkers are needed. In this study, we have chosen mass spectrometry based proteomics to profile patient plasma to discover diagnostic and prognostic biomarkers of heart failure. This experimental method allows simultaneous qualitative and quantitative analysis. Bioinformatic analysis of the protein profiles to detect protein changes has been undertaken to identify potential markers of disease. Upon method development, plasma protein profiles from one hundred acute heart failure patients were obtained using a Waters Synapt G2 QTOF mass spectrometer post plasma enrichment (ProteominerTM, Bio-Rad) and 2D-RP-RP fractionation. Samples were analysed using a HDLC-MSE experiment and run in triplicate. Statistical comparisons of the protein profiles were made using PLGS v2.5.2 and progenesis LC-MS to identify potential candidates for biomarkers. Using a label free 2D HDLC-MSE experiment we have found that differences in protein expression of acute heart failure patient profiles exist. Seven candidate proteins have been identified and are shown to be involved in many different physiological processes that play a role in the pathophysiology of heart failure. ELISA analysis of the seven identified markers has identified SAP as a strong predictor of adverse patient outcome in acute heart failure. Using multivariate analysis, SAP has been found to be an independent prognostic marker in acute heart failure patients. Further studies are needed to verify SAP as a biomarker in a larger patient cohort, and measure SAP alongside current prognostic markers. A mechanistic study to identify the role of SAP in heart failure pathology needs to be undertaken.