Shotgun analysis of plasma fibrin clot-bound proteins in patients with acute myocardial infarction

Introduction: The presence and amount of the proteins within a plasma clot may influence clot properties, like susceptibility to fibrinolysis, however, the clot proteome has not yet been extensively described. The aim of the study was to investigate the protein composition of clots of four patients with acute myocardial infarction (AMI) in two time points: in the acute ischemic phase and two months later during the standard therapy. Materials and Methods: Shotgun proteomic method (2DLC-MS/MS) was used to investigate time-dependent protein composition changes of clots prepared ex vivo from citrated plasma of the peripheral blood of patients with AMI. Results: Proteomic analysis revealed a total number of 62 proteins identified in all 8 samples grouping into several distinct functional clusters (e.g. cholesterol transporter activity, immunoglobulin binding and peptidase regulatory activity). The protein signatures of clots differed significantly depending on time after ACS, showing 30% greater variability in protein composition of the clots prepared in the plasma two months after the onset of AMI. Several proteins potentially involved in clot formation and resolution showed an interesting pattern of changes over time. Conclusion: We provided the first qualitative analysis of proteomes of fibrin clots generated ex vivo in plasma taken from patients with AMI showing differences between clots generated in the acute ischemic phase and those prepared two months later. It might be hypothesized that differences involving proteins of potential influence on within-clot fibrinolysis and clot stability may partially explain time-dependent changes in the clots structure and firmness in patients with AMI. (C) 2015 Elsevier Ltd. All rights reserved.