MOGAntikörper

MOG-Antikörper, or MOG-IgG, are autoantibodies directed against the myelin oligodendrocyte glycoprotein, a protein located on the outer surface of oligodendrocyte processes and the myelin sheath in the central nervous system. The detection of MOG-IgG defines a disease entity called MOG antibody-associated disease (MOGAD), which is considered distinct from multiple sclerosis and from aquaporin-4 antibody–positive neuromyelitis optica spectrum disorder.

The clinical spectrum of MOGAD includes optic neuritis, acute disseminated encephalomyelitis (ADEM), transverse myelitis, and brainstem or encephalitic syndromes. The presentation can be monophasic or relapsing, and pediatric cases often resemble ADEM, while adults more frequently have optic neuritis or transverse myelitis. Compared with MS and AQP4-IgG NMOSD, MOGAD shows different patterns on MRI and CSF, and the prognosis and relapse risk may differ.

Diagnosis relies on a cell-based assay using full-length human MOG to detect IgG antibodies in serum. Testing should be interpreted in the clinical context, as low-titer positivity can occur, and serostatus may change over time; persistent positivity is often used to support a chronic diagnosis. Re-testing may be considered, especially after initial pediatric presentations or relapse.

Treatment for acute attacks typically involves high-dose corticosteroids, with plasma exchange in steroid-refractory cases. For relapsing disease, long-term immunotherapy—such as rituximab, mycophenolate mofetil, azathioprine, or intravenous immunoglobulin—may be used, with therapy tailored to disease activity and patient factors. Overall prognosis is variable, but outcomes after optic neuritis in MOGAD can be favorable compared with AQP4-IgG NMOSD, though relapses can occur.