Peter K. Stys of the Hotchkiss Brain Institute, University of Calgary in his article, "Pathoetiology of multiple sclerosis: are we barking up the wrong tree?", argues that while the majority of the medical research community currently approaches MS as an autoimmune disease (much like Lupus and Rheumatoid Arthritis), for which the trigger is the immune system attacking a particular part of the nervous system, the features of the disease are equally well explained by approaching MS as a neurodegenerative disease (such as Parkinson's and Alzheimer's), which is followed by an immune reaction to damage.
This may sound like a fine distinction, but it would totally change the approach taken in treating the disease, as one would try to stop the degeneration of the nervous system rather than damp down the immune system. Neurodegenerative diseases are characterized by the breaking down of the nervous system, and although immune cell infiltration and loss of the myelin sheath that insulates nerve fibres is the hallmark of MS, more recent studies indicate that neuronal structures are also damaged.
Dr. Stys argues that as current approaches have failed to produce effective treatments, the medical research community should look afresh at alternative explanations for the disease, in order to better understand how to treat MS.