Endothelial Cell ICAM-1 Staining in Human Carotid Arteries

In this study human carotid artery specimens from 18 patients were examined by an en face technique to demonstrate the endothelial cell staining of intercellular adhesion molecule-1 (ICAM-1). Endothelial cells about the carotid bifurcation and within the post-stenotic region of the internal carotid artery were predominately polyhedral in shape with heterogenous but often intense ICAM-1 staining. Endothelium lining the partially stenosed lumen of the intern carotid orifice were elongated with ICAM-1 staining often polarized at the proximal end of the cell. There were two dominant patterns of ICAM-1 staining associated with polyhedral endothelial cells, cell border, and cell surface/nuclear profile staining. Polyhedral cells at the proximal end of the internal carotid artery stenosis appeared to have both patterns while those at the distal end were most often observed with only the cell surface expression pattern. Adherent leukocytes were mostly observed in association with polyhedral endothelial cells especially in the post-stenotic internal carotid and were uncommon within stenoses. These results indicate heterogeneity not only of endothelial cell morphology but also in the intensity and pattern of staining of ICAM-1 about atherosclerotic lesions. This may be indicative of different functional properties for ICAM-1 depending on anatomical localization and consequent hemodynamic stresses.