We next tested whether chronic exposure of primary human brain pericytes to ALS participant sera (for 96 hours) altered their subsequent response to pro-inflammatory triggers IL-1β, IFN-γ or TNF-α, in terms of cytokine intracellular expression (at 8 hours) or secretion (at 8 and 24 hours). Here, TNF is linked to amyotrophic lateral sclerosis.