Alterations in the Expression of Intercellular Adhesion Molecule-1(ICAM-1) on Neutrophils and in the Serum in the Coronary Circulationof Patients with Coronary Artery Disease

The intercellular adhesion molecule-1 (ICAM-1) is expressed on the surface of endothelial cells as well as neutrophils. Because neutrophils in the coronary circulation may play an important role in the progression of coronary artery disease, ICAM-1 and other adhesion molecules expressed on them were studied in the coronary circulation of patients with coronary artery disease. We used flow cytofluorometry to evaluate the amount of ICAM-1,CD18,and L-selectin expressed on neutrophils entering and leaving the coronary circulation in 18 patients who underwent coronary angiography. In addition, the serum level of the circulating form of ICAM-1 (cICAM-1) was measured in the same samples by using an enzyme-linked immunosorbent assay. Expression as the percentage of change between the left coronary artery and coronary sinus showed that neutrophil ICAM-1 (nICAM-1) decreased and serum cICAM-1 increased in patients with severe left coronary artery stenosis, compared with those with angiographically normal coronary arteries or only mild stenosis (nICAM-1,-9.7±2.9% vs 1.0±4.0%, p<0.05; cICAM-1,6.3±1.9% vs 0.5±1.7%, p<0.05,respectively). The changes in the expression of CD18 and L-selectin on neutrophils passing through the coronary circulation were not significant (CD18,-3.1±2.0% vs -3.8±4.3%; L-selectin, 6.0±3.6% vs -1.5±4.5%, respectively). ICAM-1 expressed on neutrophils appeared to be digested and relesed into plasma during passage through the coronary circulation in patients with severe stenotic coronary arteries. Thus, measurements of ICAM-1 may allow a prediction of the progression of coronary atherosclerosis.