Association with inflammatory cells and apolipoproteins to the progression of atherosclerosis

PURPOSE Inflammatory cells are known to be associated with the progression of atherosclerosis and plaque rupture. However, the relation to inflammatory cells and apolipoproteins on the progression of atherosclerosis is unknown. This study was aimed at examining the different expressions of inflammatory cells and evaluate the effect of apolipoprotein (APO) C1 and APO E during the progression of atherosclerosis. METHODS Ten atherosclerotic tissues were compared with five non-atherosclerotic tissues. The presence of vascular smooth muscle cells (VSMCs), macrophages, T-cells, APO C1, and APO E were identified by Western blotting and immunohistochemical analysis with antibodies. The senescence was analyzed by senescence-associated β-galactosidase. RESULTS The protein expression and senescence of macrophages, APO C1 and APO E were significantly higher in the main atherosclerotic lesion than the non-atherosclerotic lesion. A high concentration of inflammatory cells and the paucity of VSMCs were present in the shoulder area. In addition, macrophage and T-cells are expressed in the early stage of atherosclerotic development and more expanded in advanced atherosclerotic plaques. APO C1 was expressed mainly within the necrotic core, and APO E existed mostly around the necrotic core and the fibrous cap in advanced atherosclerotic plaques. CONCLUSION Our study indicated that the expression and the senescence of macrophage and T-cells may be closelyrelated to induction and deposition of APO C1 and APO E. This contributes to the development and progression of atherosclerotic plaque by expanding the necrotic core.