 The purpose of this research is to characterize the effect of teriflunomide on the activation of B-cells, as well as its capacity to modify B-cell cytokine secretion. The in-vitro identified effects of teriflunomide on the expression of B-cell activation markers, costimulatory and antigen presenting molecules, as well as on cytokine secretion, will then be confirmed in a cohort of Relapsing Remitting Multiple Sclerosis RRMS patients treated with this medication. 