The problem is that mice can't get MS. When researchers experiment on mice, they do so using animal models. With MS these models are Experimental Autoimmune Encephalomyelitis (EAE) and Theiler’s Murine Encephalitis Virus-Induced Demyelinating Disease (TMEV-IDD). Neither is MS. So if you cure a mouse with EAE, you've cured them of EAE, not MS, and there's no knowing if the same treatment works on MS in humans.