TNF and amyotrophic lateral sclerosis: Th1 cells are known to induce a microglia pro-inflammatory phenotype which can contribute to the inflammation status of the CNS in ALS patients, generating pro-inflammatory molecules such as tumor necrosis factor-alpha (TNFα); interleukin IL-6, IL-1β, and IL-12; and chemokine ligand-2 (CCL2) [61,62].