Physiologic Electrical Fields Direct Retina Ganglion Cell Axon Growth

Cell transplantation-based approaches to restore vision in patients blinded by advanced optic neuropathies show immense promise but are limited by 1) low integration efficiency and 2) of the RGCs that integrated, few axons grew out of the eye. What these experiments demonstrate is that the endogenous cues in the host retina and optic nerve are insufficient to direct the growth of newly transplanted RGC axons out of the eye. There is much interest in the potential of electrical fields (EFs) to promote long distance axon growth: axons of hippocampal neurons have grow directionally when exposed to an EF. Drawing from this, we hypothesized that EFs might exert a similar galvanotropic effect on RGC axon growth. If so, can EFs be exploited to direct RGC axon growth out of the eye.