The study on mesenchymal stem cells ameliorating experimental autoimmune encephalomyelitis

Abstract

Objective To investigate the mechanism of mesenchymal stem cells (MSC) ameliorating experimental autoimmune encephalomyelitis (EAE). Methods EAE model of C57BL/6 mice were established by the administration of MOG35-55/CFA emulsion. MSCs were purified from bone marrow of C57BL/6 mice and cultured. Then we recorded the clinical score and analyzed the pathological change of spinal cord to evaluate the state of EAE. The levels of TNF-α, IFN-γ, IL-4, and TGF-β cytokines in peripheral blood were evaluated by ELISA in EAE group, MSC-treated group, and the control group. CD4+ Foxp3+ Treg cells in these three groups were analyzed by flow cytometry. Results MSC were successfully purified and cultured. The clinical score and T-cell infiltration in spinal cord of MSC-treated mice reduced significantly. IL-4 and TGF-β in peripheral blood of the MSC-treated mice were obviously higher than those in control group(t=7.719、17.17, P<0.01) and EAE group(t=54.45、48.36, P<0.01), while IFN-γ and TNF-α were significantly lower than those in control group (t=104.90、1.998, P<0.01) and EAE group(t=270.10、13.58, P<0.01). The percent of CD4+ Foxp3+ Treg cells in spleen in the MSC-treated group was higher than that in control group(t=15.91, P<0.01) and EAE group(t=33.39, P<0.01). Conclusion The transplantation MSC can effectively improve the condition of experimental autoimmune encephalomyelitis. MSC performs the function of immunoregulation on EAE through up-regulating the anti-inflammatory cytokines (IL-4, TGF-β) and Treg cells and down-regulating the proinflammatory cytokines ( IFN-γ, TNF-α). Key words: Mesenchymal stem cell; Experimental autoimmune encephalomyelitis; CD4+ Foxp3+ Treg cells; Immunoregulation