Novel Antibodies Reveal Inclusions Containing Non-Native SOD1 in Sporadic ALS Patients
Figure 1
Micrographs of spinal cord motoneurons showing SOD1-immunoreactive inclusions.
Using the 4–20Ra-ab, 57–72Ra-ab, and 131–153Ra-ab anti-SOD1 peptide antibodies (0.64, 5 and 0.75 µg/ml, respectively) numerous small granular inclusions could be seen in tissues from sporadic (SALS) and familial (FALS) patients lacking mutations in the SOD1 gene (A, B, D, E, J-L, N and O). Note that the lipofuscin do not stain in B. As a rule motoneurons from the controls lacked inclusions (J, K), but in a few cases were a small number of granular inclusions observed (arrows in C, L). Using a sheep anti-SOD1 antibody against whole SOD1 (Calbiochem), SOD1-immunoreactive inclusions could sometimes be discerned against background staining in ALS patients with abundant small granular inclusions (F). In patients carrying the D90A mutation, small granular inclusions were the major type of inclusion (131–153Ra-ab antibody, 0.75 µg/ml) (G). Using a mutation-specific antibody (10 µg/ml) both larger skein and LBHI-like inclusions (H), as well as small granular inclusions (I), could be seen in an ALS patient carrying the G127X mutation. Sections double-labeled with the the lysosomal marker cathepsin D (M and O; red fluorescence) and the 57–72Ra-ab anti-SOD1 antibody (N and O; green fluorescence; 5 µg/ml). The merged picture of the green and red channel scans shows a partial overlap of green and red fluorescence indicating colocalization of SOD1 and lysosomes (O). Scale bar = 30 µm (in A–D, H, I), 18 µm (in E–G), 7 µm (in J), 8 µm (in K, M-O) and 11 µm (in L).