[Neuroimmunological diseases: update]

Autoimmune mechanisms are involved in the pathogenesis of several neurological diseases, called as neuroimmunological diseases. Neuromyelitis optica(NMO) has long been considered as a subset of multiple sclerosis but the primary target of NMO has recently been shown as a water channel aquaporin 4(AQP4) localized on the astrocytes. Anti-AQP4 antibody is the main pathogenic factor in NMO. Antibodies to gangliosides and ganglioside complexes are involved in the pathogenesis of Guillain-Barré syndrome and Fisher syndrome. Efficacy of high-dose chemotherapy with autologous peripheral blood stem cell transplantation for POEMS syndrome has been reported. Presence of anti-MuSK antibodies and anti-Lrp4 antibodies was shown in some of the patients with anti-AChR antibody-negative myasthenia gravis. Several novel autoantibodies have been reported in some neuroimmunological diseases affecting central nervous system. Nationwide surveys have recently been performed for several neuroimmunological diseases in Japan.