Scientists Are Rewinding the Biological Clock Inside Human Eyes—and Patients Say They Can See Again

3 min readThe eye is a complicated organ, and damage or disease to any piece of this optical puzzle can have serious consequences. The build-up of protein and lipid deposits, known more commonly as drusen, starves retinal epithelium cells, leading to macular degeneration. An accumulation of proteins behind the eye’s lens can lead to cataracts. Random genetic mutations can kill light-sensitive photoreceptors, inflicting retinitis pigmentosa. Fluid buildup in the eye can damage the optic nerve and the retinal ganglion cells that feed it. The result is glaucoma, which slowly erodes the peripheral vision of millions of Americans.All of these maladies are difficult to treat in different ways, but the era of regenerative medicine and gene therapy holds immense promise for each one. For example, scientists worldwide are racing to use stem cells to replace—or even rejuvenate—cells damaged by macular degeneration and retinitis pigmentosa. And now, Life Biosciences has administered a gene therapy to patients in hopes that epigenetic reprogramming can turn back the clock on aging ganglion cells, whose axons form the optic nerve fiber layer and whose dysfunction drives glaucoma.“While this Phase 1 study is designed to evaluate safety and tolerability, the preliminary observations of visual field improvements in two participants are encouraging as we continue to advance the ER-100 program,” Sharon Rosenzweig-Lipson, chief scientific officer at Life Biosciences, said in a press statement. “This milestone marks an important step in Life Bio’s progress translating epigenetic restoration into a new class of medicines for age-related diseases.”This gene therapy, known as ER-100, is based on the work of David Sinclair, a geneticist at Harvard Medical School and co-founder of the Boston-based start-up. In 2020, Sinclair, along with lead author Yuancheng Lu and a team of colleagues from Harvard Medical School, published a study in the journal Nature detailing how the expression of three transcription factor genes restored youthful attributes to the ganglion cells of mice models. Time Magazine reports that the technique used six years later in human subjects remains remarkably similar, and eight weeks after receiving the initial treatment, two of the three participants showed meaningful improvement.“In places where they weren’t seeing as well, or weren’t identifying lights, we are now seeing better evidence that they can,” Rosenzweig-Lipson tells Time. Similarly, in a phase 1/2a medical trial for treating macular degeneration with transplanted stem cells at the University of Michigan, researchers were initially only concerned with proving the safety of the procedure, but found that participants were already reporting significant vision improvements.In a recent interview with Innovation & Tech, Sinclair also states that this approach could have therapeutic advantages far beyond just the eye.“The basic machinery we are engaging exists in cells throughout the body, and age-related epigenetic changes occur across tissues, so the underlying principle should not be unique to the eye,” he says. “We are already seeing encouraging preclinical signals in very different organs, including the liver, which suggests this could become a platform, rather than a medicine only for the eye.”For the entirety of human history, vision loss has been an inevitable byproduct of aging. But by unlocking the regenerative power of biology, what was once inevitable is quickly becoming less so.Darren lives in Portland, has a cat, and writes/edits about sci-fi and how our world works. You can find his previous stuff at Gizmodo and Paste if you look hard enough.