ICAM-1

Overview
ICAM-1 is a type of intercellular adhesion molecule continuously present in low concentrations in the membranes of leukocytes and endothelial cells. Upon cytokine stimulation, the concentrations greatly increase. ICAM-1 can be induced by interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFα) and is expressed by the vascular endothelium, macrophages and lymphocytes.

ICAM-1 has been implicated in subarachnoid hemorrhage (SAH). Levels of ICAM-1 are shown to be significantly elevated in patients with SAH over control subjects in many studies. While ICAM-1 has not been shown to be directly correlated with cerebral vasospasm, a secondary insult which affects 70% of SAH patients, treatment with anti-ICAM-1 reduced the severity of vasospasm.