Proteomic analysis of plasma from patients during an acute coronary syndrome.

OBJECTIVES The aim of this study was to analyze modifications in the plasma protein map during an acute coronary syndrome (ACS) using proteomics. BACKGROUND Proteomics is a new technology that allows the detection and identification of several proteins at a given time in a sample. METHODS Plasma from 19 patients, 11 with acute myocardial infarction (AMI) and 8 with unstable angina (UA), was investigated. The control group included nine age-matched volunteers. RESULTS In two-dimensional electrophoresis using a pH range of 4 to 7, constant differences were found in at least four different areas within the plasma protein map. In area 1, we identified the presence of seven alpha(1)-antitrypsin (AAT) isoforms in plasma from control subjects. alpha(1)-antitrypsin isoform 1 was undetectable in plasma from UA and AMI patients. The AAT isoforms 5, 6, and 7 were reduced in plasma from AMI patients when compared with UA patients. Three fibrinogen gamma chain isoforms were identified in area 2. Fibrinogen gamma chain isoforms 1 and 2 were increased in AMI patients with respect to UA patients. Five apolipoprotein A-I isoforms were identified in area 3. All of them were reduced in plasma from AMI patients with respect to UA patients. In area 4, the gamma-immunoglobulin heavy chains were detected and were found increased in plasma from ACS patients. CONCLUSIONS Plasma proteomic analysis makes it possible to develop a map of the protein isoforms that are expressed in plasma during an ACS.