Down-regulation of IRF3 expression in Relapse-Remitting MS patients

Background: Relapsing-Remitting (RRMS) is the most common Multiple Sclerosis disease course. Interferon regulatory factor 3 (IRF3) as major regulators of immune system genes plays a critical role in the activation of type I interferons promoters, in particular IFNβ promoter. Hence we aimed to evaluate the expression rate of IRF3 in RRMS patients under different type of IFNβ treatment. Material and methods: In the present study total of 100 subjects participated. Blood samples of 25 patients with RRMS newly diagnosed who have not been treated with interferon components, 25 patients with RRMS treated with Interferon beta-1α (B1a), 25 patients with RRMS treated with Interferon beta-1β (B1b) and 25 control samples were collected. The samples were transferred at standard conditions to the Cellular and Molecular Research Center of Shahrekord University of Medical Sciences, RNA was extracted and converted to cDNA. To evaluate the expression of IRF3 the Real-Time PCR method using SYBR Green dye was done. The level of gene expression was measured by a comparative threshold cycle formula. The obtained data were analyzed using SPSS v15 software. Results: In the study we compared the IRF3 mRNA expression of all subjects in association with gender, which no significant difference was seen (P > 0.05). Also assessment of the gene mRNA level in study groups revealed that the B1b, B1a and new case group had the lowest expression respectively. Moreover, comparison of the mRNA level between new case and B1b groups showed remarkable difference (P 0.05). Conclusion: Perhaps the IFNβ recombinants decreases the IRF3 expression as a negative feedback mechanism. Overall the data reported here, supports the previous studies in important role of IRF3 in autoimmune inflammatory disease of CNS and Multiple Sclerosis.