Fig. 1.

Identification of an iper-oxidized SOD1 in a subset of sALS patients. (A) Representative immunoblot of SOD1 oxidation detected by a derivatization assay of carbonyl compounds. Proteins extracted from sALS, fALS, and healthy control lymphoblasts, before and after H₂O₂ treatment, were precipitated with rabbit anti-SOD1 antibody and analyzed by Western blot using anti-DNPH (Upper) and sheep anti-SOD1 (Lower) antibodies. (B) Ratio of DNPH and precipitated SOD1. For each patient's line, samples were analyzed in triplicate in three independent blots (with and without H₂O₂), and densitometric analysis was performed on each blot. The graph represents the mean ± SD SOD1 oxidation for each experimental group. ANOVA revealed significantly higher oxidized SOD1 in a group of sALS lymphoblasts compared with lymphoblasts from mutSOD1-fALS and healthy controls (*P < 0.05). (C) Representative blot of derivatization assay of carbonyl compounds on total protein content from fALS, sALS, and healthy control lymphoblasts before and after H₂O₂ treatment, showing no differences in total oxidation levels.