ABSTRACT
Objective To investigate the correlation between the expression of adhesion molecule CD146 and the vulnerability of carotid atherosclerotic plaque.Methods The plaque samples were collected from 40 patients who underwent the carotid endarterectomy and were divided into the stable plaque group and the instable plaque group by ultrasound imaging.Five carotid artery samples were taken from the healthy donors as the control.Immunohistochemistry was applied to test the CD146 expression in all samples.Results Higher expression of CD146 was observed in the atherosclerotic plaques than in the healthy control.Moreover,statistical difference was found in the expression of CD146 in the plaques between the instable plaque group and the stable plaque group (0.31 ± 0.19 vs 0.17 ± 0.07,P ＜ 0.05).The expression of CD146 was positively correlated with the necrotic area (r =0.471 8,P =0.019 9) and the matrix metalloproteinase (MMP)-9 expression in the plaques (r =0.535 6,P =0.000 9).Conclusion The CD146 expression is correlated with the vulnerability of carotid atherosclerotic plaque.
ABSTRACT
PURPOSE: We sought to evaluate enhancement of plaque with gadolinium-based contrast agent by magnetic resonance imaging (MRI) in comparison with histopathology, namely lipid-rich and macrophage-rich components that were two representative characteristics of plaque vulnerability using atherosclerotic rabbit aorta in order to determine which histopathologic component is relevant to the enhancement. MATERIALS AND METHODS: New Zealand white rabbit (n=4, weight 3.0 to 3.5 kg, all male) was used for animal model of atherosclerosis. Atherosclerotic aortic lesions were induced by high-cholesterol diet and double balloon injury. T1-weight axial images were acquired before and after gadolinium-based contrast agent using a 3-T MRI. MR images and the matched histopathological sections (n=35) were divided into 4 quadrants or 3 (n=130). Enhancement ratio (ER, ER=SIpost/SIpre) on MRI was calculated for each quadrant and compared with histopathology in regard to lipid-rich and macrophage-rich areas. RESULTS: Lipid-rich quadrants were 72 and fibrous quadrants were 58. The number of quadrants which had macrophage-rich areas was 105 and that of quadrants which did not have macrophage-rich areas was 25. ER was significantly higher in lipid-rich quadrants than in fibrous quadrants (mean ER 2.25+/-0.41 vs. 2.72+/-0.65, p=0.013). ER poorly correlated with macrophage-rich areas when lipid-component was controlled (correlation coefficient -0.203, p=0.236). CONCLUSION: Lipid-rich plaques showed stronger enhancement than fibrous plaques using a standard gadolinium-based extracellular contrast agent. Macrophage infiltration did not correlate with degree of enhancement. Further study is warranted that account for optimal time of imaging after contrast injection using various plaque models from early to advanced stages and all possible parameters associated with contrast enhancement.