In a breakthrough that could transform regenerative medicine, researchers at Harvard Medical School have successfully used partial epigenetic reprogramming to restore youthful vision in aged non-human primates, bringing the technology one step closer to human application.
The study, led by Professor David Sinclair, used gene therapy to deliver three Yamanaka factors (Oct4, Sox2, and Klf4 — collectively known as OSK) to the retinal ganglion cells of aged macaques with glaucoma-like vision loss. Within eight weeks, treated eyes showed significant regeneration of optic nerve fibers and restoration of visual acuity.
"This is the first demonstration of epigenetic reprogramming reversing age-related disease in a primate," said Professor Sinclair. "The implications extend far beyond vision — this same approach could potentially rejuvenate any tissue in the body."
The treatment works by resetting the epigenetic marks — chemical modifications on DNA that change how genes are expressed — to a younger state, without reverting cells all the way back to stem cells. This partial reprogramming preserves cell identity while restoring youthful function.
A human clinical trial for age-related vision loss is expected to begin enrollment next year. Meanwhile, Sinclair's lab is expanding the approach to other organ systems, including the brain and joints, in ongoing primate studies.