Abstract 4008: PSGL-1-Expressing CD4 T Cells are Enriched in Culprit Coronary Artery Lesion of Acute Coronary Syndrome
Background: Recently, several evidences on the crucial role of adhesion molecules in the development of atherosclerosis and plaque instability have been reported. While expression of VCAM-1, ICAM-1 and L-selectin has been consistently observed in atherosclerotic plaques it is still uncertain how adhesion molecules on T cells contribute to the incidence of acute coronary syndrome (ACS). In this study, we examined whether adhesion molecules on T cells in ACS have a significant role in the plaque stability and prone to cause ACS.
Methods and Results: Fresh CD4 T cells were isolated from the peripheral blood of 76 ACS patients (AMI=35, UAP=41) and 74 age-matched controls (NC). CD69, an activation marker of T cells, was strongly expressed on CD4 T cells from ACS than from NC by FACS (P<0.0001). CD4 T cells from ACS highly expressed p-selectin glycoprotein ligand-1 (PSGL-1) and integrin β (CD18), but not L-selectin by FACS (P < 0.03, P < 0.01, n.s., respectively). Soluble PSGL-1 (sPSGL-1) levels in plasma were lower in ACS patients than in NC (P=0.0001), which correlated negatively with the PSGL-1 expression on CD4 T cells (R=0.405, P<0.02). We further investigated the thrombus-aspirating device samples (n=14) and fresh CD4 T cells derived from both the coronary artery and peripheral blood from the each same patient with ACS. CD4 T cells from the coronary artery strongly expressed PSGL-1 (P<0.002), but not integrin β (CD18) and L-selectin by FACS. Finally, PSGL-1 was expressed on T cells, but not on CD68 positive macrophage, MPO positive neutrophil, or CD41 positive platelets in the thrombus-aspirating device samples.
Conclusions: From these results, we demonstrated that PSGL-1-expressing CD4 T cells are enriched in the culprit coronary artery lesion of ACS, contributing to the acceleration of plaque instability and occurrence of ACS.