GPNMB and amyotrophic lateral sclerosis: Six proteins were differentially abundant in the CSF EV proteome in the sub-group of ALS associated with the C9orf72 hexanucleotide repeat (FDR-adjusted p < 0.1), including upregulation of Transmembrane glycoprotein NMB (GPNMB, Q14956) and Protein-glutamine gamma-glutamyltransferase 2 (TGM2, P21980), and downregulation of Annexin 11 (ANXA11, P50995), Ubiquitin-like modifier-activating enzyme 1 (UBA1, P22314), Cytochrome b-245 heavy chain (CYBB P04839), Cofilin-1 (CFL1; Fig. 7a).