Science Alert reports on a successful experiment that has restored vision to multiple people with cornea damage by using a new stem-cell transplant technique:
Four participants were involved in the study, all of whom suffer from a disorder that causes scar tissue buildup on the cornea, called limbal stem cell deficiency (LSCD).
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This crucial framework also contains a hearty supply of stem cells, which are ready to replenish any worn-out units in the cornea, like little windshield wipers, keeping the glass clear of fogginess as we age.
Without the vigilance of the limbal stem cell community, gradual vision loss is inevitable.
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That’s where the potential of induced pluripotent stem cells ( iPSCs) comes into play.
These all-powerful units are converted from the cells of any human’s body. Once reprogrammed back into an embryonic-like state, they propagate indefinitely, with the ability to shapeshift into any type of adult human cell, including those of the cornea.
In 2023, researchers in the US announced they had used limbic stem cells to restore vision in two patients with corneal damage up to a year later.
Now, scientists at Osaka University Hospital in Japan have gone a step further and used iPSCs, derived from healthy human blood cells, to restore vision.
In the lab, the resulting iPSCs were coaxed into corneal epithelial cell sheets (iCEPS). These sheets were then transplanted over the patients’ cornea after scar tissue was removed, and a protective contact lens topped it off.
Some seven months after the transplant, all four patients showed improvements to their vision. A year after, however, the vision of patient 4, a 39-year-old woman with the most severe vision loss of the cohort, had once again regressed.
The best improvements to vision were seen among patients 1 and 2, a 44-year-old woman and a 66-year-old man, respectively.
Researchers suspect patients 3 and 4 may have not shown the same improvement because of an insidious immunological response to the transplant. None of the patients were given immunosuppressive drugs, apart from steroids.
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You can read more of the vision-restoring research here, in The Lancet.