In particular, decreasing CX3CL1 and increasing CX3CR1 were found in TG mice during ALS progression late in the disease, and this imbalanced CX3CL1/CX3CR1 axis seems to be closely related to the microglia M1/M2 imbalance (Zhang J. et al., 2018). Here, CX3CL1 is linked to amyotrophic lateral sclerosis.