TNF and amyotrophic lateral sclerosis: These events may interfere with the balance between death/survival signaling pathways in TNFα-activated Schwann cells (Tang et al., 2013), possibly altering the normal functions of activated Schwann cells and leading to a failure of trophic surveillance and/or to toxicity signaling in ALS (Ranganathan and Bowser, 2003; Cova et al., 2010).