To ascertain that the lesions observed in the NMO-rats were directly due to the presence of AQP4-IgG, we infused three rats with IgGAQP4+ previously depleted in AQP4-IgG (IgGAQP4+dep adsorption on HEK-AQP4 cells—Fig. 8e). This evidence concerns the gene AQP4 and neuromyelitis optica.