title: Expression of stromal-cell-derived factor-1 on circulating platelets is increased in patients with acute coronary syndrome and correlates with the number of CD34+ progenitor cells.
abstract: OBJECTIVE
  Previous experimental studies have suggested that platelet stromal-cell-derived factor-1 (SDF-1) regulates mobilization and recruitment of haematopoietic progenitor cells supporting revascularization in mice. However, there are no clinical data available regarding platelet-bound SDF-1 in patients with acute coronary syndrome (ACS). The objective of this study was to evaluate the platelet-surface expression of SDF-1 in patients with ACS.
  
  
  RESULTS
  Patients with ACS (n = 418) showed a significantly enhanced SDF-1 expression on admission compared with those with stable angina pectoris (SAP, n = 486) [SAP (mean fluorescence intensity (MFI) +/- SD): 13.48 +/- 5.27; ACS: 18.45 +/- 12.85; P < 0.001) independent of cardiovascular risk factors and medication. Enhanced platelet-bound SDF-1 expression was found in patients with reduced left ventricular ejection fraction (LVEF <55%) in comparison to patients with normal LVEF (P = 0.005). Platelet-bound SDF-1 expression positively correlated with the degree of platelet activation [CD62P: r = 0.325; glycoprotein VI (GPVI): r = 0.277; PAC-1: r = 0.501; P < 0.001 for all] and showed a significant, but slight association with plasma levels of SDF-1 (r = 0.084; P = 0.045). In a subgroup of patients with coronary artery disease, platelet-bound SDF-1, but not other platelet activation markers, significantly correlated with the number of circulating CD34(+) progenitor cells (r = 0.252; P = 0.002) or CD34(+)/CD133(+) endothelial progenitor cells (r = 0.352; P = 0.008).
  
  
  CONCLUSIONS
  Platelet-bound SDF-1 may play an important role in peripheral homing of circulating progenitor cells thus in tissue regeneration.
authors.affiliation: Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, Eberhard Karls-Universität Tübingen, Tübingen, Germany. konstantinos.stellos@med.uni-tuebingen.de
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Stellos
authors.forename: Boris
authors.initials: B
authors.lastname: Bigalke
authors.forename: Harald
authors.initials: H
authors.lastname: Langer
authors.forename: Tobias
authors.initials: T
authors.lastname: Geisler
authors.forename: Annika
authors.initials: A
authors.lastname: Schad
authors.forename: Andreas
authors.initials: A
authors.lastname: Kögel
authors.forename: Florian
authors.initials: F
authors.lastname: Pfaff
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Stakos
authors.forename: Peter
authors.initials: P
authors.lastname: Seizer
authors.forename: Iris
authors.initials: I
authors.lastname: Müller
authors.forename: Patrick
authors.initials: P
authors.lastname: Htun
authors.forename: Stephan
authors.initials: S
authors.lastname: Lindemann
authors.forename: Meinrad
authors.initials: M
authors.lastname: Gawaz
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood* / Q000503:physiopathology; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets / Q000378:metabolism*; D002452:Cell Count; D054377:Chemokine CXCL12 / Q000097:blood*; D005260:Female; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000097:blood / Q000503:physiopathology
chemical_list: D018952:Antigens, CD34; D015415:Biomarkers; D054377:Chemokine CXCL12