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[Immunohistochemical analysis of adhesion molecules in directional coronary atherectomy specimens]
1Third Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto.
Insights
Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM) are linked to macrophages in atherosclerotic plaques and restenosis. These adhesion molecules may play a role in active ischemic heart disease.
Area of Science:
- Cardiovascular Biology
- Immunohistochemistry
- Atherosclerosis Research
Background:
- Chronic inflammation drives atherosclerotic plaque progression and restenosis post-coronary angioplasty.
- Adhesion molecules are critical mediators of inflammatory processes in vascular disease.
Observation:
- Directional coronary atherectomy specimens from patients with acute coronary syndromes, old myocardial infarction, and stable angina were analyzed.
- Immunohistochemical staining identified the distribution of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM) within lesions.
- Cellular characterization used markers for macrophages (CD68), endothelial cells (CD31), and smooth muscle cells (alpha-smooth muscle actin).
Findings:
- Macrophage-rich areas were prevalent in lesions from acute coronary syndromes and early restenotic lesions.
- ICAM-1 and VCAM expression strongly correlated with macrophage-rich areas.
- ICAM-1 staining was generally more intense than VCAM staining, except in one restenotic lesion.
Implications:
- Macrophages expressing ICAM-1 and VCAM are likely significant contributors to unstable plaques and restenotic lesions.
- Understanding these adhesion molecules may offer insights into the active disease processes of ischemic heart disease.
- Targeting ICAM-1 and VCAM could be a potential therapeutic strategy for managing atherosclerotic disease progression and restenosis.
Abstract:
Chronic inflammatory cells are key components in the progression of atherosclerotic plaques and restenosis after coronary angioplasty. Adhesion molecules are fundamental in inflammatory processes. Therefore, the distributions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM) were investigated in directional coronary atherectomy specimens obtained from 14 patients, in 6 with acute coronary syndromes (myocardial infarction and unstable angina within 1 month), 6 with old myocardial infarction and 2 with stable effort angina. There were eight primary lesions and six restenotic lesions. Atherectomy tissue fragments were snap frozen and cut into 4 microns thick cryostat sections for immunohistochemical staining by avidin-biotin complex immunoperoxidase techniques using adhesion molecule specific monoclonal antibodies BBIG-I1 (ICAM-1) and BBIG-V1 (VCAM). The cells of lesions were characterized in sequential sections by macrophage marker KP1 (CD68), endothelial marker JC/70A (CD31), and smooth muscle cell marker 1A4 (alpha-smooth muscle actin). Four restenotic lesions that had undergone a prior balloon angioplasty within a few months consisted of intimal proliferation and the other lesions were atherosclerotic plaque. Macrophage-rich areas were seen in the lesions from acute coronary syndromes and/or early restenotic lesions. Expression of ICAM-1 or VCAM was strongly associated with macrophage-rich areas, but VCAM staining was weaker than ICAM-1 except in one restenotic lesion. Macrophages that express ICAM-1 and/or VCAM may be important in the unstable plaques and restenotic lesions related to disease activity of ischemic heart disease.