Because our pilot experiments strongly suggested a key role for microglia in driving IL-6 and IL-8 secretion in C9-ALS, the screen was performed in both C9-ALS SMs and in C9-ALS microglia similarly aggregated in 3D (microglia spheroids containing 7,500 cells/spheroid). This evidence concerns the gene CXCL8 and amyotrophic lateral sclerosis.