AQP4 and nervous system disorder: Three of the five altered proteins in AQP4-IgG+ NMOSD patients were also detected as transcripts in the MS brain tissue: glial fibrillary acidic protein (GFAP) was upregulated in active, inactive and remyelinating lesion types, inter-alpha-trypsin inhibitor heavy chain H2 (ITIH2) was significantly upregulated in all lesion types, while actin cytoplasmic 1 (ATCB) was not differently expressed compared to non-neurological-disease WM brain areas (Fig. 7b).