In addition, high levels of proinflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL) 1 beta, and interferon gamma (IFN-γ) have been identified in the cerebrospinal fluid (CSF) of ALS patients [20], and an increased amount of IL-6 was observed in astrocyte-derived exosomes of patients suffering from ALS [21]. Here, IL6 is linked to amyotrophic lateral sclerosis.