MOG and transverse myelitis: Myelin oligodendrocyte glycoprotein-associated disorders (MOGAD) is an autoimmune central nervous system disease characterized by optic neuritis, transverse myelitis, and/or encephalitis in the context of serological autoantibodies against myelin oligodendrocyte glycoprotein (MOG), expressed in the outermost layer of the myelin sheath by oligodendrocytes.