GFAP and amyotrophic lateral sclerosis: These data consisted of digitally extracted features (i.e. stain-positive superpixel counts, a measurement of stain abundance) from stained motor cortex (BA4) of the same C9-ALS-FTSD cohort included in the current study, and included Iba1 (i.e. homeostatic microglia), CD68 (i.e. activated macrophage), GFAP (i.e. activated astrocyte) and pTDP43 (i.e. phosphorylated TDP-43 aggregate) staining.