However, PBMCs activation against the selected HERV-K env peptides displayed a greater expression of the chemokine MCP-1 in HCs compared to ALS patients with a significant difference, both for HERV-K env 19–37 (ALS vs. HCs, mean ± SD = 0.102 ± 0.038 vs. 0.726 ± 0.21; p = 0.023) and HERV-K env 109–126 (ALS vs. HCs, mean ± SD = 0.107 ± 0.058 vs. 0.352 ± 0.11; p = 0.039) (Figure 3b). Here, CCL2 is linked to amyotrophic lateral sclerosis.