CD8A and psoriatic arthritis: Psoriatic arthritis was originally considered to be a Th1-mediated disease.[10] However, GFAP was reported to be mediated by GFAP peptide-specific cytotoxic CD8+ T cells in a transgenic mouse model of autoimmune GFAP meningoencephalitis.[11] Therefore, further investigation is needed to determine whether shared immunoinflammatory pathways trigger the coexistence of both diseases.