National Geographic reports on efforts to rejuvenate cells while preserving their specialized identity

National Geographic reports on efforts to rejuvenate cells while preserving their specialized identity

The report examines partial cellular reprogramming, an attempt to return an old or damaged cell to a younger state while preserving its specialized identity, at several scales. These range from a trial in one eye to claims about rejuvenating the entire body.

On August 6, National Geographic published a report on partial cellular reprogramming. Its clinical focus is ER-100, an experimental gene therapy administered to one eye. The trial is enrolling people with open-angle glaucoma or ischemic optic neuropathy, which is damage caused by impaired blood supply to the optic nerve. The ClinicalTrials.gov registry lists a planned enrollment of up to 18 participants. On June 9, Life Biosciences announced that the first participant had received ER-100. The report presents this ongoing trial as one possible route toward cellular rejuvenation.

ER-100 is administered to one eye. The treatment uses a modified virus to deliver instructions for producing three proteins, OCT4, SOX2 and KLF4, collectively known as OSK. These proteins regulate which genes are active in a cell. Eight weeks of doxycycline treatment activate their production. During the first phase, physicians are selecting a dose and assessing safety, including how well participants tolerate the treatment. Their health and vision will be monitored for up to five years.

This approach grew out of a 2020 experiment in mice. In retinal cells, OSK shifted chemical marks on DNA that regulate gene activity toward a younger state. It also stimulated the regrowth of neuronal projections after injury and improved vision in mice with a laboratory model of glaucoma. The eye provides a confined area in which this approach can be tested in humans for the first time.

Sinclair explained the choice of the eye to the report's author as follows:

“The FDA likes interventions that can be confined to one isolated area of the body because that is safer. We decided that the eye was an excellent place to start.”

The report also discusses more distant plans. Cellular reprogramming researcher Juan Carlos Izpisua Belmonte speaks about building a foundation for future medicine, while Sinclair describes SL-100 as a program for rejuvenating the entire body. The trial involving one eye is therefore presented alongside laboratory projects and claims about interventions affecting the whole body.

Shinya Yamanaka links aging to several processes. Epigenetic marks that regulate gene activity change, DNA becomes damaged, and mitochondrial function and the environment surrounding cells also change. He expects future strategies to combine several approaches. He also calls for public discussion of the consequences of substantially extending human life.

“Substantial life extension may affect questions of human existence and values more deeply than AI,” Yamanaka says.