In an in vitro genetic model of amyotrophic lateral sclerosis (ALS), where the mutated SOD1G93A is specifically expressed by astrocytes, Sun et al. (2013) reported that conditioned medium from mesenchymal stem cell (MSC) cultures increased CX3CL1 and reduced TNFα, IL6, and iNOS expression on astrocytes, and mediated a protective effect towards primary motor neurons. This evidence concerns the gene TNF and amyotrophic lateral sclerosis.