Soluble ICAM-1 sICAM

ICAM-1 An adhesion protein of the capillary endothelium. Its synthesis is increased following stimulation by TNF-a. It is related in the blood and CSF as soluble ICAM-1 (sICAM-1). The brain capillaries are rich in ICAM-1, and even a single lesion visible by magnetic resonance imaging results in elevated serum concentrations. 

ICAM-1 and lymphocyte function-associated protein (LFA)-l pathway are involved in monocyte-endothelium interaction during a cholesterol-rich diet. In rats on high-cholesterol diet, ICAM-1 expression was increased on aortic EC, which was associated with increased monocyte adherence (more than 85% of adherent macrophages exhibited LFA-1 antigen and injecting the animals with ICAM-1 monoclonal antibody and LFA-1 monoclonal antibody reduced mostly LFA-1 positive macrophages) (167). In clinically healthy middle-aged men, levels of soluble ICAM-1 (sICAM-1), but not sVCAM-1 or E-selectin, were associated with subclinical atherosclerosis and inflammatory variables (168). 

The intracellular adhesion molecule-1 (ICAM-1) is an important protein of endothelial cells. Its expression is induced by the proinflammatory cytokines IL-I, TNF-a, and INF-y during the early phase of the inflammatory process. Under these conditions, its soluble form, sICAM-1, is released intrathecally at a high rate, probably originating from the endothelial cells of the inflamed tissue (i.e., the meninges and adjacent brain parenchymal tissue). 

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