Fig. 3

CSF of ALS cases contains the species recognized by misfolded SOD1-specific antibody C4F6. The CSF samples (20 μg of total proteins, 100 μL of volume) from Non-ND, PD/DLB, PSP, AD, and ALS cases were analyzed by a sandwich ELISA with (a) C4F6 and (b) FL-154 as capture antibodies, and Pan-SOD1 was used as a detection antibody. As described in the Methods, absorbance values at 490 nm measured in the ELISA were substituted into equations fitted to standard curves (Additional file 3: Figure S2), and apparent amounts of SOD1 were thereby estimated and plotted as SOD1 (ng/20 μg of total CSF proteins). The data on the PD and PSP cases containing the C4F6-reactive SOD1 (also see Fig. 4) were shown in black filled circles. Three independent experiments were performed to estimate error bars (standard deviation). The statistical differences were analyzed with Mann-Whitney U-test, and P values are shown