MOG and myelitis: MOG-IgG3 antibodies have previously been reported in three patients with negative results for total MOG-IgG, as determined by a non-subclass-specific assay, in one study [24]; in three out of 15 patients with discordant results from three different non-subclass-specific CBAs in a second study [6]; and, at high titre (1:3200), in a single patient with ON and myelitis with patchy cord lesions [32].