SERPINA3 and amyotrophic lateral sclerosis: Notably, we identified proteins shown to be differentially regulated in ALS before [9, 21, 51–54], e.g., cystatin C (CST3: -log10 FDR = 2.11, log2 fold change (FC) = -0.41, FC = -1.33), calmodulin (CALM: -log10 FDR = 5.08, log2 FC = -0.46, FC = -1.38), alpha-1-antichymotrypsin (SERPINA3: -log10 FDR = 2.50, log2 FC = -0.34, FC = -1.27) and clusterin (CLU: -log10 FDR = 2.10, log2 FC = -0.38, FC = 1.30) were significantly lower abundant, while gelsolin isoform 2 (GSN: -log10 FDR = 2.30, log2 FC = 0.31, FC = 1.24) was more abundant in ALS TF compared to controls (Data S1).