CNTF and eye disorder: Recent studies have found that Ciliary neurotrophic factor (CNTF) gene therapy can induce optic nerve regeneration in animal models, making it the drug of choice for treatment of a variety of eye diseases, while C–C motif chemokine ligand 5 (CCL5) can induce extensive axon regeneration and mediate the effect of CNTF gene therapy (Xie et al., 2021).