Yamanaka Factors (OSK) — Epigenetic Partial Reprogramming
Yamanaka factors (OSK) refer to the transcription factors Oct4, Sox2, and Klf4, which can partially reprogram adult cells to a more youthful epigenetic state without erasing their cellular identity. This transient reprogramming approach holds significant promise for reversing age-related decline and restoring tissue function in vivo.
Mechanism of Action
The OSK factors are master transcription factors that remodel the epigenome, reversing age-associated DNA methylation changes and restoring youthful gene expression patterns. Unlike full reprogramming with OSKM (which includes the oncogene c-Myc), partial reprogramming with OSK avoids inducing pluripotency and teratoma formation. By transiently expressing these factors, cells undergo epigenetic rejuvenation, leading to improved mitochondrial function, reduced senescence, and enhanced regenerative capacity, while maintaining their original somatic lineage.
Human Trial Evidence
No published human longevity trials. Animal/in-vitro evidence only. Preclinical studies in mice have demonstrated that transient OSK expression can restore vision in glaucoma models, promote optic nerve regeneration, and safely reverse epigenetic clocks in multiple tissues.
Dosing Protocol
Unestablished in humans. Currently restricted to preclinical research using viral vectors (e.g., AAVs), lipid nanoparticles, or mRNA delivery systems for transient, tightly controlled expression in animal models.
Safety & Contraindications
Highly experimental with significant theoretical risks in humans, including the potential for oncogenesis, teratoma formation, and loss of cellular identity if expression is not perfectly controlled. Delivery methods, tissue targeting, and precise dosing durations remain major safety hurdles before clinical translation.