OSK reprogramming restored sight in aged/glaucoma mice (Lu et al., Nature 2020)
Sinclair's lab (Lu et al., Nature 2020) showed that expressing three Yamanaka factors (Oct4, Sox2, Klf4 = OSK) in mouse retinal ganglion cells restored youthful DNA-methylation patterns, regrew optic-nerve axons, and reversed vision loss in a glaucoma model — the first demonstration that a complex mammalian tissue can be safely "reset" to a younger state. A long-term functional follow-up was reported at ARVO 2023.
Using an adeno-associated virus to deliver three of the four Yamanaka reprogramming factors (Oct4, Sox2, Klf4 — "OSK," deliberately omitting c-Myc to avoid tumor risk) into the retinal ganglion cells of mice, Sinclair's lab restored youthful DNA-methylation patterns, triggered regrowth of damaged optic-nerve axons, and reversed vision loss in both an aging model and an induced-glaucoma model. It was the first demonstration that partial reprogramming could safely and functionally "reset" a complex tissue in a living mammal, rather than merely shifting a molecular marker.
Why it matters (spine): this is the foundational result the entire partial-reprogramming field points back to. Nearly every downstream claim about age-reversal — including the 2026 human IND clearance — traces its scientific credibility to this paper and its follow-ups, not to any commercial product. It is independently published, peer-reviewed, and has held up well enough to justify moving into human trials six years later.
Live status / Provenance: Yuancheng Lu, Bruce A. Brommer, David A. Sinclair et al., Nature 588, 124–129 (2 Dec 2020), Sinclair lab, Harvard Medical School (credited). A longer-term functional follow-up was reported at the Association for Research in Vision and Ophthalmology (ARVO) 2023 meeting, extending confidence in durability. This is the strongest, most independently corroborated result in the Sinclair longevity portfolio.
So we should file this as HKG's anchor evidence for partial reprogramming's real biology, distinct from and prior to any commercial claim, and track independent replication attempts as the highest-value falsification watch in the garden.
Treat partial reprogramming as the real, load-bearing science under the longevity hype — and the thing to track hardest as it moves into humans.
domains: longevity · epigenetics · aging · regenerative-medicine