Multiple sclerosis (MS) is a severely debilitating disease that causes muscle weakness and wasting. It is an autoimmune disease, meaning that the body’s own immune system attacks the myelin that wraps the long neural extensions from the spinal cord to the muscles. Without myelin, the communication between spinal cord and muscle is impaired, and the affected individual experiences severe muscle weakness. The disease is either progressive, with unrelenting degradation of muscle function, or “relapsing-remitting”, which is a more common form of the disease in which patients can experience intermittent recover of function. We are developing a stem cell based therapy for MS, testing the effects of neural cells derived from human embryonic and induced pluripotent stem cells in an experimental mouse model that mimics many of the clinical signs of MS. In our first year,we have perfected the production of the neural cells and performed a large set of initial transplantation experiments. Our results so far are very promising, suggesting that during certain stages of their differentiation, human pluripotent stem cell-derived neural cells positively affect clinical symptoms in the mouse model when they are transplanted to the spinal cord.