Association between P-selectin glycoprotein ligand-1 and pathogenesis in acute coronary syndrome assessed by optical coherence tomography.

OBJECTIVE

Although monocytes appear to be actively involved in the onset of acute coronary syndrome (ACS), they are heterogenous in human peripheral blood. How up-regulation of monocyte subsets leads to coronary plaque rupture followed by thrombus formation remains unclear. Recent studies have shown that P-selectin glycoprotein ligand-1 (PSGL-1) is involved in monocyte activation in patients with thrombus formation. We therefore investigated the relationship between the expression of PSGL-1 on monocyte subsets and thrombus formation using frequency-domain optical coherence tomography (FD-OCT) in patients with ACS.

METHODS

We enrolled a total of 100 individuals in this study: patients with acute myocardial infarction (AMI, n=25), unstable angina pectoris (UAP, n=20), or stable angina pectoris (n=35) who underwent coronary angiography, and control subjects (n=20). Three monocyte subsets (CD14++CD16-, CD14++CD16+, and CD14+CD16+) and the expression of PSGL-1 were measured by flow cytometry. In patients with AMI and UAP, FD-OCT was performed before percutaneous coronary intervention.

RESULTS

Circulating peripheral CD14++CD16+ monocytes expressed PSGL-1 more frequently than CD14++CD16- and CD14+CD16+ monocytes in patients with ACS. The expression of PSGL-1 on circulating peripheral CD14++CD16+ monocytes was significantly elevated in patients with AMI compared with the other 3 groups. Moreover, the expression levels of PSGL-1 on CD14++CD16+ monocytes were significantly higher in patients with plaque rupture or intracoronary thrombus assessed by FD-OCT.

CONCLUSION

Up-regulation of PSGL-1 on CD14++CD16+ monocytes may be a crucial role in plaque rupture and thrombus formation.