These are pathogenic mechanisms that depend on the antibody Fc region of IgG1-3 subclass antibodies, such as acetylcholine receptor (AChR) antibodies in myasthenia gravis, NMDAR antibodies in autoimmune encephalitis or of antibodies against aquaporin 4 (AQP4) in neuromyelitis optica. Here, AQP4 is linked to neuromyelitis optica.