TNF and myeloid sarcoma: In MS, astrocytes transform to the A1 phenotype [9], secreting several neurotoxic cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6, leading to the formation of a proinflammatory milieu in the CNS and the subsequent myelin injury as well as impaired remyelination process [10].