IFNG and amyotrophic lateral sclerosis: A significant difference in the expression of IFN-γ by CD8+ T cells was observed after stimulation with HERV-K env 19–37 peptide in ALS patients with respect to HCs with a statistically significant p value (ALS vs. HCs, mean ± SD = 0.582 ± 0.385 vs. 0.044 ± 0.022; p = 0.017) (Figure 3c).