In spite of important therapeutic advances during the last 20 years, coronary atherothrombotic complications are and will remain the first cause of death all over the world. Acute coronary syndromes (ACS) are unpredictable and can lead to sudden death before any medical treatment. The development of new strategies for the screening of patients susceptible to develop an ACS is thus of major interest.

We hypothesized that coronary artery disease, in its stable and unstable forms, is associated with modifications of the concentrations of various circulating proteins (circulating proteome), which could be assessed using a new method for pre-treatment of plasma (equalization) before differential proteomic analysis.

Every step from blood sampling to the proteomic analysis (nature of the tubes used, centrifugation time and speed, conditions of storage etc.) was strictly standardized

Three groups of 30 patients were studied: non-ST elevation myocardial infarction (group 1), stable angina (group 2), angiographically normal coronary arteries without extra-coronary atherosclerosis (group 3). Five milliliters of plasma from each patient were equalized; this methodology (ProteominerTM, Biorad) is based on a solid-phase ligand library of hexapeptides which provides a potential ligand for every protein in the biological sample, with a limited capacity of binding for abundant proteins, thus allowing enrichment in low abundance proteins/peptides. Various strategies of elution have been used in order to increase the number of peaks/spots detected by SELDI-TOF mass spectrometry and by 2D-electrophoresis, respectively. Several differential peaks are currently being identified.

The screening, prognostic and therapeutic values of the new biomarkers discovered using this novel approach will require further validation, using more straightforward assays (eg, ELISA) in case-control and prospective cohorts of patients with coronary artery disease.