Soluble Fas levels in cerebro spinal fluid and serum of patients with multiple sclerosis and other neurological diseases

The process of apoptosis, or programmed cell death, is involved in the regulation of the immune response and in the elimination ot potentially autoreactive T-cells. Regulation of apoptosis can take place via interaction of Fas and Fas hgand; elevated levels of the soluble form of Fas (sFas) have been reported in sera of patients with autoimmune disorders. We assessed the levels of CSF and serum sFas antigen in 45 MS patients, 49 patients with other neurological disease and in sera of 40 healthy controls. Soluble Fas antigen was detected using a commercially available ELISA kit. In serum, no differences were detected between MS patients and controls. However, a statistically significant increase of sFas levels in patients with inflammatory disease was detected in sera. CSF sFas levels were similar between MS patients and patients with non-inflammatory neurological diseases, while a trend to increased levels in CSF of patients with inflammatory diseases was observed. However, a statistically significant correlation between CSF sFas level and BBB damage (AlbCSF/AlbS) was detected in non-MS neurological disease, but not in MS patients. The normalized ratio (sFasCSF/sFasSerum)/(AlbCSF/AlbSerum) was calculated and used as marker of intrathecal synthesis of sFas (Fas Index); a statistically significant increse in Fas Index was detected in MS patients compared to patients with noninflammatory neurological disease (11.20±7.55 vs 6.77±5.48; p