MOG (myelin oligodendrocyte glycoprotein) is a myelin-associated glycoprotein expressed on the outer membrane of myelin sheaths in the central nervous system 1. The protein contains a single N-glycosylation site at Asn(31) 2 and functions in CNS development and T cell receptor signaling 3. MOG serves as a receptor for rubella virus according to UniProt annotations. MOG is the primary autoantigen in MOG antibody-associated disease (MOGAD), a distinct demyelinating disorder now recognized as separate from multiple sclerosis and neuromyelitis optica 3. Anti-MOG autoantibodies are predominantly IgG1, a T cell-dependent immunoglobulin subclass 3. MOG-specific antibodies mediate CNS demyelination through both complement-dependent and Fc-receptor-dependent mechanisms, with FcR interactions particularly important for T cell activation 4. Pathological analysis reveals MOG-dominant myelin loss with preserved oligodendrocytes and perivenous demyelinating patterns characteristic of ADEM, distinct from AQP4-associated pathology 5. Clinically, MOGAD presents with optic neuritis, myelitis, encephalomyelitis, and cortical encephalitis with predominantly CD4+ T cell and macrophage infiltration 5. Live cell-based assays for MOG-IgG detection show superior sensitivity (95.1%) compared to fixed assays (45.7%), important for accurate diagnosis 6. MOG-CAR regulatory T cell therapy represents a promising therapeutic approach for autoimmune demyelination 1.