( the normal light-detecting protein in ...)'Prosthetic' retinal cells let blind mice see light

Finally, they wrote, it remains unclear which of the many inherited retinal diseases might be treatable by using the technique. "The remodeling of inner retinal neurons triggered by photoreceptor degeneration has raised some concerns for the retinal-based rescue strategy after the death of photoreceptors," wrote Pan and colleagues. "However, retinal degenerative diseases are heterogeneous as to the time course of the degeneration, survival cell types, and, possibly, their functional state. Therefore, further studies are required to evaluate what types of retinal degenerative diseases and/or what disease stages are suitable for this potential treatment strategy," they wrote.

However, noted the researchers, their technique avoids some problems presented by other approaches to restoring vision in such diseases. These approaches include transplantation of normal photoreceptor cells into the eye or implantation of electronic retinal "chips" to replace the photoreceptor function.

"An important advantage of the strategy sought in this study is that it does not involve the introduction of tissues or devices into the retina and, therefore, may largely avoid the complications of immune reactions and biocompability," wrote the researchers. "In addition, it could potentially achieve high spatial resolution for the restored 'vision' because the approach targets the cellular level. Thus, the expression of microbial-type channelrhodopsins, such as ChR2, in surviving retinal neurons may be another potential strategy for the treatment of complete blindness caused by rod and cone degeneration," they wrote.