Three blind mice could be a thing of the past. Scientists have restored the sight of blind mice by implanting tiny gold prosthetic photoreceptors into their eyes.
So far, this incredible technique has only been carried out on mice. However, the work holds some hope for people with degenerative eye diseases such as retinitis pigmentosa or macular degeneration.
The revolutionary study comes from a team of scientists from Fudan University in Shanghai, China. They have managed to develop gold nanoparticle coated titanium dioxide nanowires that work just like the eye’s natural photoreceptors, as described in the latest issue of the journal Nature Communications.
The gold-coated nanowires, no longer than 100 nanometers in length, sit in the place of rod and cone photoreceptor cells at the back of blind mice retinas. When light hits these artificial nanoparticles, it generates a small voltage, sparking a response from neurons in the visual system, just like normal.
The beauty of this technique is that it doesn’t require additional micro-electronic gadgets to do its job, unlike most other current eye prosthetics.
Jiayi Zhang and his team of neurobiologists checked for activity within the retinal ganglion cells, a type of neuron in the retina of the eye that receives visual information from photoreceptors, and found that they were reacting when exposed to green, blue, and ultraviolet light. They also tested for sight the old-fashioned way, by shining a light at the eye and seeing if the pupil dilated.
All in all, this confirmed that the mice could detect light and were no longer blind.
“Some of the implanted eyes reached the same level of [pupil light reflex] as that in wild-type mice, indicating the recovery of light sensitivity in multiple colors,” the study authors note. Although the mice cannot see in full-color yet, the researchers believe it will be possible to obtain color vision if they develop nanowires that are sensitive to specific colors.
Crucially, the mice also appeared to tolerate the treatment fairly well, showing little discomfort.
It’s early days for this amazing piece of nanotechnology, but the researchers remain confident it could be used to help treat humans with macular degeneration, retinitis pigmentosa, or forms of blindness associated with the loss of photoreceptor cells.
An equally remarkable study from 2016 managed to restore the vision of blind rats using CRISPR, a novel method that snips strands of DNA and replaces them with new genetic material. Once again, it is too early to make too many promises, but rest assured scientists across the world are working hard on the case.
