Correlation between monocyte chemoattractant protein-1/chemokine (C-C motif) ligand 2 and coronary plaque characteristics

In this work, our primary objective was to examine the interrelationship among the serum level of chemokine (C-C motif) ligand 2 (CCL2) and plaque characteristics in coronary culprit lesions. The clinical data of 116 coronary heart disease patients who were hospitalized in the Department of Cardiology of Henan Province People's Hospital from February 2015 to June 2017 were retrospectively analyzed. The study population was subdivided according to the concentration of CCL2 into low CCL2 group and high CCL2 group. The levels of blood lipid, creatinine, and uric acid were measured, and patients underwent coronary angiography. The characteristics of the culprit lesions were detected by intravascular ultrasound, and the correlation between the serum markers and the characteristics of coronary artery plaque was analyzed. Moreover, the coronary artery disease dataset from the Gene Expression Omnibus database was downloaded and the genes regulated were analyzed by CCL2 using gene set enrichment analysis (GSEA). Patients with high CCL2 group had higher LDL-C level and L/H ratio, and lower HDL-C level than the low CCL2 group. Compared with low-level CCL2 group, coronary plaque in the high CCL2 group had higher eccentric plaque and plaque rupture, and thin cap fibroatheromas, fibrofatty and necrotic core and lower fibrous tissue. CCL2 was positively correlated with the percentage of fibrofatty and necrotic core, and negatively correlated with the percentage of fibrous tissue. Furthermore, GSEA analysis showed that samples with high CCL2 expression were enriched for genes involved in different pathways, such as cell adhesion molecules and Nod-like receptor signaling pathway. The CCL2 level was correlated with vulnerable plaques of coronary artery and had certain value in detecting vulnerable plaques. These results indicated that CCL2 could be regarded as a clinical prognostic biomarker for coronary artery disease. Impact statement Vulnerable plaques are plaques which are susceptible to rupture or thrombosis and trigger a series of adverse events such as coronary disorders. CCL2 is a soluble basic protein belonging to the CC subfamily. Previous studies have been investigated on the correlation between inflammatory factors and clinical events, but there are few studies on the correlation between CCL2 and plaque characteristics. Our study found that the high expression of CCL2 is involved in multiple processes in the genesis and progression of coronary artery disease, and would be a potential clinical prognostic indicator. In addition, high expression of CCL2 may be related to gene pathways such as Nod-like receptor signaling pathway, suggesting that CCL2 is involved in the inflammatory response and immune process of coronary artery disease.