Evaluation of the effect of DMF and Ruxolitinib combinational therapy on Experimental autoimmune encephalomyelitis (EAE) as a muose model of Multiple sclerosis (MS)

Abstract

Multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE) are chronic neurological disease in young adults that is characterized by inflammation and demyelination of the central nervous system (CNS). The pathogenesis of ms is much more complex process, which is mediated by various immune cells including CD4+ T cells, CD8+ T cells and B cells. Evidence from several studies have implicated CD4+ Th cells play critical role in the pathogenesis of MS. Among various groups of CD4+ Th cells, Th17 cells play an important role in MS. Th17 cells are involved in MS disease severity and activity with secretion of pro-inflammatory cytokines, such as IL-17. Th-17 / Treg balance plays an important role in MS, and in this study we examined the concomitant therapeutic effect of two compounds; Ruxolitinib and DMF that are able to alter this balance in EAE mice. Materials and Methods: C57BL/6 mice (6–8 weeks old) were used in our study. Mice were injected with MOG peptide along with complete freund’s adjuvant and M. tuberculosis. They received the DMF and Ruxolitinib according to the protocol for 14 days. After 14 days of treatment, the mice were sacrificed and the spleen, spinal cord, and brain were removed for testing. The expression proinflammatory and anti-inflammatory cytokines, such as IL-10 and IL-17A, was analyzed by real-time PCR. The frequency of TH17 cells and Tregs was assessed by flow cytometry. Findings: Ruxolitinib and DMF decreased the inflammation and demyelination rate in EAE mouse model. Our results also showed that the percentage of Th-17 cells in CNS decreased significantly in the group treated with combination therapy compared with the control group, while the percentage of Treg cells increased. Inflammatory cytokine levels after combination therapy was significantly lower than in control group, while the IL-10 anti-inflammatory cytokine levels were higher than in the control group.