The cellular immunology of multiple sclerosis

Multiple sclerosis (MS) is a neurological disease that affects the central nervous system (brain and spinal cord) resulting in debilitating motor and sensory dysfunction, Its mean age of onset is 30 years and, with the except ion of trauma, MS remains the most frequent cause of neurological disabilit ies for young adults. The disease is highly variable in its onset and progr ession. It may not be easily diagnosed, at least in its earliest stages. Si gnificant disability is a hallmark. of RIS. Indeed, up to 50% of patients r equire walking aids and 10% ape wheelchair-bound at 15 years after an initi al diagnosis. Clinical features include deficits in sensory (parasthesias a nd numbness), motor (difficulties with fine movements and gait), balance, b ladder, and sexual functions, Although the etiology for MS is not yet knows , it is thought to be related to microbial, genetic, and/or environmental f actors, Pathologically, RIS is characterized Ly inflammation. An influx of mononuclear cells occurs through a disrupted blood-brain barrier into an im mune-privileged central nervous system, The secretion of a variety of infla mmatory cytokines and chemokines from glial cells leads to loss of myelin, disruption of oligodendrocyte integrity, and axonal loss. These events, in large measure, affect progressive neural atrophy. How brain inflammatory ac tivities affect transendothelial migration of leukocytes into the,rain and alter the process of myelination are the focal points for MS research activ ities.