Multiple Sclerosis (MS) is an auto-immune neurodegenerative disease that affects more than 400,000 individuals in the United States, and 2.5 million worldwide (www.nationalmssociety.org). The main pathogenic mechanism in MS involves an inflammatory condition that damages the myelin of the central nervous system (CNS), resulting in axonal damage and neurological impairment, often leading to severe disability. MS is one of the most common causes of neurological disability in young and middle-aged adult individuals, and as such has a tremendous physical, psychological and social impact on patients' lives. MS is a complex disease diagnosed by McDonald criteria with different clinical and pathological phenotypes. Several forms of MS have been described: Relapsing-Remitting (RRMS), Secondary-Progressive MS (SPMS), Progressive-Relapsing MS (PRMS), and Primary-Progressive MS (PPMS).