Gene Therapy Gives Primates Young Eyes Again

Scientists have developed a new gene therapy that can reverse vision loss in primates, potentially laying the groundwork for treatments in humans as well. Last month, a team of scientists from Harvard Medical School and biotech company Life Biosciences announced preclinical data showing that a new approach was able to reprogram genetic markers to restore visual function in primates that had their eyes damaged with lasers.

In essence, the team injected their eyes with special chemicals that can partially reprogram cells to have them return to a more youthful state — a decidedly “Blade Runner” approach to vision restoration, if it’s born out by future research. The study involved ten primates, six of which were treated with the new gene therapy, while four had a control solution injected into their eyes. The eyes of the primates that received the treatment over five weeks ended up responding much better to light stimulation. The health of their eyes’ nerve fibers improved significantly as well, signs that are consistent with the restoration of vision. The overall goal was to address a specific eye disorder called non-arteritic anterior ischemic optic neuropathy (NAION), which is essentially the equivalent of a stroke but for the eye, and which results in a sudden loss of vision.

NAION is the most common cause of acute optic neuropathy in people over 50, but currently has no effective treatment,” said Bruce Ksander, study co-lead and associate professor of ophthalmology at Harvard, in a press release, adding that the new therapy “can lead to significant recovery in affected visual function in a [primate] model of NAION.” “That potential unlocks new opportunities for cellular rejuvenation, not just in NAION but in other ophthalmic diseases that occur as a result of retinal ganglion cell dysfunction as we age,” he added.

While we’re still a long way from establishing whether a similar technique can be effective in humans — besides, the researchers’ results have yet to be published and peer-reviewed — it’s a hopeful first step.


Rejuvenation by Controlled Reprogramming

On 19 January 2022, co-founders Rick Klausner and Hans Bishop publicly launched an aging research initiative called Altos Labs, with $3 billion in initial investment from backers including tech investor Yuri Milner and Amazon founder Jeff Bezos. This is the latest in a recent surge of investment in ventures seeking to build anti-aging interventions on the back of basic research programs looking at epigenetic reprogramming. In December, cryptocurrency company Coinbase’s cofounder Brian Armstrong and venture capitalist Blake Byers founded NewLimit, an aging-focused biotech backed by an initial $105 million investment, with the University of California, San Francisco’s Alex Marson and Stanford’s Mark Davis as advisors.

The discovery of the Yamanaka factors’ — four transcription factors (Oct3/4, Sox2, c-Myc and Klf4) that can reprogram a differentiated somatic cell into a pluripotent embryonic-like state — earned Kyoto University researcher Shinya Yamanaka a share of the Nobel prize in 2012. The finding, described in 2006, transformed stem cell research by providing a new source of embryonic stem cell (ESC)-like cells, induced pluripotent stem cell (iPSCs), that do not require human embryos for their derivation. But in recent years, Yamanaka factors have also become the focus for another burgeoning area: aging research.

So-called partial reprogramming consists in applying Yamanaka factors to cells for long enough to roll back cellular aging and repair tissues but without returning to pluripotency. Several groups, including those headed by Stanford University’s Vittorio Sebastiano, the Salk Institute’s Juan Carlos Izpisúa Belmonte and Harvard Medical School’s David Sinclair, have shown that partial reprogramming can dramatically reverse age-related phenotypes in the eye, muscle and other tissues in cultured mammalian cells and even rodent models by countering epigenetic changes associated with aging. These results have spurred interest in translating insights from animal models into anti-aging interventions. “This is a pursuit that has now become a race,” says Daniel Ives, CEO and founder of Cambridge, UK-based Shift Bioscience.

The Yamanaka factors that can reprogram cells into their embryonic-like state are at the heart of longevity research

We’re investing in this area [because] it is one of the few interventions we know of that can restore youthful function in a diverse set of cell types,” explains Jacob Kimmel, a principal investigator at Alphabet subsidiary Calico Life Sciences in South San Francisco, California. The zeal is shared by Joan Mannick, head of R&D at Life Biosciences, who says partial reprogramming could be potentially “transformative” when it comes to treating or even preventing age-related diseases. Life Biosciences, a startup co-founded by David Sinclair, is exploring the regenerative capacity of three Yamanaka factors (Oct4, Sox2 and Klf4).