Detectable concentrations of Fas ligand in cerebrospinal fluid after severe head injury.

When the cell surface molecule Fas is triggered by its agonist Fas ligand the result is apoptosis of these cells and tissue destruction. To elucidate the pathophysiological relevance of Fas ligand in patients with cerebral oedema caused by trauma, we examined its concentrations in cerebrospinal fluid in 18 patients using specific ELISA. Serum and cerebrospinal fluid from healthy people and injured patients without head trauma did not contain detectable Fas ligand. In contrast, cerebrospinal fluid from patients with severe brain injury contained high concentrations of Fas ligand without detectable concentrations in serum. Soluble Fas ligand concentrations in cerebrospinal fluid correlated significantly with severity of brain injury. The Fas-Fas ligand-system may have a pivotal role in causing oedema and local tissue destruction in the brain after severe head injury.