CMKLR-1 Expression in Human Aorta Is Dominated by Smooth Muscle Cell Positivity

Chemokine-like receptor 1 (CMKLR-1) is a G-protein-coupled receptor that functions as the binding site of chemerin. It induces chemotaxis in various immune cells, and it has recently been linked to vascular remodeling in inflammation. In this study, we investigated CMKLR-1 expression in human aorta samples, focusing on its distribution across different cell types and its potential association with clinical and histomorphological data, particularly concerning aortic dissection and aneurysms. We analyzed 62 aorta samples taken from patients undergoing dissection surgery (n = 27) or aneurysm/dilatation (n = 35) using immunohistochemical CMKLR-1 staining. CMKLR-1 expression was primarily observed in the smooth muscle cells (SMCs) of the aortic media layer, and band-like coloring appeared in the unstained center section. CMKLR-1 positivity in the inner and outer parts of the media layer was observed in only a few cases. One-third of the vasa vasorum exhibited staining. Staining in lymphocytes, macrophages, and endothelia was rare. No significant differences in CMKLR-1 expression were found between the dissection and aneurysm cases, and the clinical or histomorphological data. Although CMKLR-1 expression did not distinguish between the studied conditions, its presence in the aortic media, especially in SMCs, is noteworthy.