Atefeh Faraz, Reza Yari, Mohammad Taheri, Mir Davood Omrani, Mohammad Saberi, Mehrdokht Mazdeh, Arezou Sayad
"Multiple sclerosis (MS) is the most common chronic inflammatory demyelinating disease of the central nervous system (CNS). The exact immunopathogenic mechanisms are not known but there is some evidence that this severe disease is more likely to develop in genetically predisposed individuals, possibly in association with environmental factors Elimination of autoreactive T cells by activation induced cell-death (AICD) is considered to be one of major process in MS. The aim of this study were to evaluate expression level of FasL in whole blood from patients with Relapsing-Remitting (RR) form of MS, and to survey the association of FasL expression with risk, Expanded Disability Status Scale (EDSS) and duration of the disease. We compared FasL expression in 50 RR-MS patients with 50 healthy controls by Taqman Real time PCR technique. Albeit there was an expression decrease, no statistically significant difference was found between total RR-MS patients and controls. However, our results showed a clear association between decrease of FasL expression in females especially older than 40 years with risk of the disease (p= 0.04, 95% CI= 0.387-1.14; p= 0.003, 95% CI= 0.139-3.12, respectively). Moreover, there was not a significant correlation between EDSS and duration of the disease and FasL expression. This finding make a valuable question what is the principal concept for this significant association between FasL expression and risk of RR-MS in females who are older than 40 years. In this study, we failed to draw an exact expression– phenotype correlation which may be due to limited statistical confirmation as a result of the small sample size and needs more investigation. These findings may possibly reflect differences in the pathogenic mechanisms associated with the failure of AICD observed in this group of MS patients."