Glutamic acid decarboxylase autoantibodies and neurological disorders.
Glutamic acid decarboxylase (GAD) is the enzyme that catalyses the production of GABA, a major neurotransmitter of the central nervous system. Antibodies to GAD (GAD-Ab) were first recognised in a patient affected by stiff-person syndrome; subsequently they were reported in a large number of cases with type 1 diabetes. Recently GAD-Ab have been described in a number of patients affected by chronic cerebellar ataxia, drug-resistant epilepsy and myoclonus. These cases usually harbour other autoantibodies or are affected by organ-specific autoimmune diseases. The role of GAD-Ab is still unclear; the lack of experimental models makes it difficult to investigate their potential pathogenetic role. However two mechanisms have been suggested: the reduction by GAD-Ab of GABA synthesis in nerve terminals or the interference with exocytosis of GABA.
Vianello
M
M
Department of Neurology and Psychiatry Sciences, Second Clinic, University of Padua, Via Vendramini 7, I-35121 Padua, Italy.
Tavolato
B
B
Giometto
B
B
D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002524:Cerebellar Ataxia / Q000097:blood / Q000276:immunology; D002908:Chronic Disease; D004827:Epilepsy / Q000097:blood / Q000276:immunology; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006801:Humans; D009422:Nervous System Diseases / Q000097:blood / Q000276:immunology*; D016884:Polyendocrinopathies, Autoimmune / Q000097:blood / Q000276:immunology; D016750:Stiff-Person Syndrome / Q000097:blood / Q000276:immunology
D001323:Autoantibodies; D015415:Biomarkers; D005968:Glutamate Decarboxylase