Restoring vision with optogenetics

Good news!

"Optogenetic therapies, which aim to restore lost vision by introducing light-sensitive proteins into damaged retinal neurons, are moving quickly toward the clinic. Several companies are developing viruses that carry genes encoding the proteins into cells that have been damaged by diseases such as retinitis pigmentosa and macular degeneration. Other approaches pair gene therapies with goggles that deliver precise flashes of light to activate the protein more effectively."

"... results of the trial are not yet published, but in January the US Food and Drug Administration (FDA) designated the treatment as a ‘regenerative medicine advanced therapy’, which should accelerate its development. It marks a significant step in the 20-year pursuit of optogenetic therapies for RP. Clinical trials have previously had mixed success, with several companies exiting the space.

Now, many academic and industry researchers are investigating variations on the idea ... Differences include which light-sensitive protein is introduced; which cells this protein is placed in; and whether to use auxiliary technologies such as goggles that deliver precise flashes of light to better activate the protein. ...

RP [retinitis pigmentosa] is a collection of genetic conditions caused by hundreds of mutations in more than 80 genes, and preventing carriers from going blind could require tailored approaches for each form. Optogenetic therapy, however, is designed to restore lost vision, and therefore could help anyone with RP. ..."

Nature Briefing: Translational Research

Restoring vision with optogenetics [seems to be an overview article] "Trials of therapies that enhance the light-sensitivity of cells in the retina are returning surprisingly positive results in people with retinitis pigmentosa."

Cones Derived from Human Stem Cells Help Mice See Again

Good news! Hopefully, we can soon say goodbye to macular degeneration and other eye diseases!

Don't forget to thank or pray for all these guinea pigs (mice), we have used to improve our lives!

"Age-related macular degeneration and other macular diseases result in the loss of light-sensing cone photoreceptors, causing irreversible sight impairment. ... Here, we show restoration of visual function after transplantation of purified human pluripotent stem cell-derived cones into a mouse model of advanced degeneration. Transplanted human cones elaborate nascent outer segments and make putative synapses with recipient murine bipolar cells (BCs), which themselves undergo significant remodeling. Electrophysiological and behavioral assessments demonstrate restoration of surprisingly complex light-evoked retinal ganglion cell responses and improved light-evoked behaviors in treated animals. ..."

Cones Derived from Human Stem Cells Help Mice See: Study | The Scientist Magazine® Researchers insert functioning cone photoreceptors into the retinas of mice with advanced eye disease, improving their vision.

Here is the link to the underlying research article:

Restoration of visual function in advanced disease after transplantation of purified human pluripotent stem cell-derived cone photoreceptors (open access)

Researchers restore lost sight in mice, offering clues to reversing aging

Amazing stuff!

"... The study suggests that hallmarks of aging, and possibly the keys to reversing it, lie in the epigenome, the proteins and other compounds that decorate DNA and influence what genes are turned on or off. ...
The idea that aging cells hold a memory of their young epigenome “is very provocative,” ...
The team focused specifically on neurons at the back of the eye called retinal ganglion cells. ... There’s a stark divide between youth and age in these cells: An embryonic or newborn mouse can regenerate the optic nerve if it gets severed, but that ability vanishes with time. ...
The injection prevented some damaged retinal ganglion cells from dying and even prompted some to grow new axons reaching back to the brain, the team reports today in Nature. ..."

"Ageing is a degenerative process that leads to tissue dysfunction and death. A proposed cause of ageing is the accumulation of epigenetic noise that disrupts gene expression patterns, leading to decreases in tissue function and regenerative capacity. Changes to DNA methylation patterns over time form the basis of ageing clocks ...
Using the eye as a model CNS [Central Nervous System] tissue, here we show that ectopic expression of Oct4 (also known as Pou5f1), Sox2 and Klf4 genes (OSK) in mouse retinal ganglion cells restores youthful DNA methylation patterns and transcriptomes, promotes axon regeneration after injury, and reverses vision loss in a mouse model of glaucoma and in aged mice. "

Researchers restore lost sight in mice, offering clues to reversing aging | Science | AAAS Researchers reversed damage to the mouse eye ... by genetically reprogramming neurons that make up the optic nerve.

Here is the respective research paper:

Reprogramming to recover youthful epigenetic information and restore vision