Adult Retinal Ganglion Cell Axon Regeneration and Re-innervation

Retinal ganglion cell (RGC) degeneration is one of the major causes for blindness, a condition widely attributed to the pathology of RGC axons. How to promote the affected RGC axons to regenerate is currently under intense investigation. Difficulties in adult RGC axons to regenerate are due partially to the attenuated intrinsic re-growth ability, and further complicated by factors located in the unfavorable microenvironments, especially the myelin sheath and the activated glia cells. Additionally, axon damage often induces RGC death, eliminating any chance for axon regeneration, and therefore further complicates the treatment for RGC degeneration. In this review, we discuss the different aspects that cause regeneration failure in the RGC axons, and also the currently known factors that promote RGC axon regeneration ability. These findings are encouraging and open the possibility that clinically meaningful regeneration may become achievable one day in the future.