IL15 and relapsing-remitting multiple sclerosis: The susceptibility of CD8 T cells of patients with RRMS to DHODH inhibition was confirmed in vitro, as the proliferation of EM and TEMRA CD8 T cells in response to TCR and IL-15 stimulation was blunted by teriflunomide, and the inhibition of proliferation can be reversed by added uridine (Supplementary Figure 2).