Fig. 5

Most of SOD1 in CSF from ALS were recognized by misfolded SOD1-specific antibody C4F6. C4F6-crosslinked magnetic beads were first incubated with CSF (40 μL) at 4 °C for 24 h, and the solutions were collected as the “unbound” fraction. The remaining magnetic beads were then treated with 10 μL of 100 mM citrate buffer at pH 3.1 in order to elute SOD1 proteins captured by the magnetic beads (the “bound” fraction). Ten microliter of CSF (input), the unbound, and the bound fractions were analyzed by Western blotting with FL-154 antibody. The percentage of C4F6-reactive SOD1 in the CSF samples was roughly estimated by measuring the band intensity of SOD1 in the unbound and bound fractions and indicated at the bottom of each gel. Details were described in the Methods