The loss of photoreceptor cells caused by retinal degenerative diseases leads to blindness. The optogenetic approach for restoring vision involves converting the surviving inner retinal neurons into photosensitive cells, thus imparting light sensitivity to the retina following the loss of photoreceptor cells. Our first demonstration of the feasibility of such an approach involved expressing ChR2 in the retinal ganglion cells of blind mice; since then, optogenetic vision restoration has been demonstrated by using a variety of optogenetic tools, especially microbial channelrhodopsins (ChRs). A ChR-based optogenetic therapy for treating blindness has advanced to clinical trials. In this chapter, we review our early proof-of-concept study of optogenetic vision restoration. We also discuss our studies for developing better ChR tools and for restoring intrinsic visual processing features in retinas with degenerated photoreceptors.
Keywords: Adeno-associated virus; Center-surround receptive field; Channelrhodopsins; Microbial rhodopsin; ON and OFF response; Optogenetics; Retinal degeneration; Sustained and transient response.