[Immunological aspects of amyotrophic lateral sclerosis]

Amyotrophic lateral sclerosis (ALS) is a devastating human neurologic disorder which causes atrophy and weakness of skeletal muscles leading to death. Although pathogenesis of most cases of ALS is not known yet, large number of evidence suggest autoimmune mechanisms through clinical, pathological, and laboratory findings, for example, high frequency of the presence of serum monoclonal gammopathy, association of thyroid diseases, and lymphocytic infiltration of brain and spinal cord tissues of patients. Especially recent findings of IgG antibodies against calcium channels and IgM anti-GM1 antibodies are important to elucidate the pathogenesis of ALS. Although conventional immunotherapy may not be effective, multifocal motor neuropathy (MMN) which simulates ALS should be carefully examined because MMN is a treatable disorder.