New Markers in Atherosclerosis: Thrombospondin-2 (THBS-2) and Leukocyte Cell-Derived Chemotaxin-2 (LECT-2); An Immunohistochemical Study

BACKGROUND: Current research investigating the role of THBS2 and LECT-2 in atherogenesis is very limited. Therefore, we designed this study to demonstrate the role of THBS-2 and LECT-2 in atherosclerosis at the tissue level in fresh specimens.
MATERIAL AND METHODS: A total of 32 patients who underwent coronary bypass surgery were enrolled. Aortic wall punch biopsies were obtained at the site of proximal aortosaphenous bypass graft anastomosis. A specimen of left internal mammarian artery (LiMA) was taken from the segment just proximal to its anastomosis. The aortic tissue is representive of the atherosclerotic tisue, and LiMA tissue is representative of the non-atherosclerotic area. The specimens were painted with CD68 for macrophage, and THBS-2 and LECT-2 antibodies for immunohistochemical staining.
RESULTS: Aortic THBS-2 levels were significantly lower, whereas aortic LECT-2 levels were significantly higher when compare to LiMA (14.4±9.9 (5–30) and 36.9±13.0 (5–60) p: 0.0001 and 20.3±15.0 (5–60) and 20.8±13,8 (10–30) p: 0.0001, respectively). CD68+ and monocyte level correlated significantly with AHA atherosclerosis grade (p=0.01, r=0.45 and p=0.001, r=0.56, Spearman’s test). CD68+ level correlated significantly with LECT-2 levels in atherosclerotic aortic tissue (p=0.026, r=0.392, Spearman’s test), whereas aortic TSBN-2 levels were not.
CONCLUSIONS: The present study has taken the first steps to highlight new markers in atherosclerosis by using immunohistochemical method. The study results suggest that the tissue levels of THBS2 and LECT-2 may correlate with the stage of atherosclerosis.

Keywords: Aorta, atherosclerosis, Chemotaxis, Leukocyte, Thrombospondins