The blood cells of a 80-year-old person in a Petri dish suddenly began to behave as if they were less than twenty. The epigenetic marks that usually accumulate over the years had almost disappeared. This is not a fantasy or a promise of eternal youth — it is the result of a precise experiment at the University of Bonn, published in the journal Aging Cell in 2026.
Researchers led by Professor Oliver Brüstle took blood cell precursors from donors ranging from newborns to 101 years old and, using two proteins — SOX2 and cMYC — directly converted them into neural stem cells. The process took more than a hundred days and occurred gradually: after just twelve days the cells had acquired stem-cell characteristics, and the epigenetic age continued to decline for weeks afterward. Ultimately, in cells from a 80-year-old donor it dropped below twenty years, and in some lines — to five percent of the original age.
Importantly, the rejuvenation proceeded without obligatory rapid cell division. Even when reproduction was artificially slowed, the epigenetic clocks continued to "rewind." This distinguishes the method from classical reprogramming via pluripotent stem cells, where changes occur faster but less controllably. The Bonn group bypassed the intermediate stage and was able to observe exactly how gene activity and nuclear structure change.
They checked not only the marks on DNA. The scientists assessed genome damage, mitochondrial function, the system for disposing of cellular "garbage," and the shape of the nucleus. By all these parameters, the rejuvenated cells from elderly donors looked close to young ones. However, epigenetic age is only one of the indicators. It does not guarantee that the cell has completely rid itself of all the consequences of aging or that such changes are stable in the body.
The resulting neural stem cells could become a model for studying brain diseases, primarily Alzheimer's disease. They can be used to test substances that accelerate or slow epigenetic shifts. But this is a laboratory tool, not a therapy. The study does not show how to restore youth to a person, and does not promise a cure for age-related diseases in the coming years.
The experiment emphasizes that aging is not a single irreversible process, but a set of parallel changes, some of which can be reversed under controlled conditions. The question remains open: which of these changes are truly important for health, and whether they can be safely corrected in a living organism. For now, one thing is clear: between molecular "rejuvenation" in a test tube and a real slowing of human aging lies a long path of research still ahead.
