Blood cells could control your ageing

Human blood cells have an intrinsic clock that remains steady even after transplant, and could control human ageing as well as underlie blood cancers. The study measured cellular age in blood cells transplanted from healthy donors to leukemia patients, focusing on donor-recipient pairs of very different ages.

“This study is related to the fountain of youth,” said Shigemi Matsuyama, an associate professor at Case Western Reserve University in the US. “We found young blood cells stay young in older people. There was no accelerated ageing of young blood cells in an older human body,” Matsuyama said. The team found the other direction was also true -- blood cells from adult donors transferred to a child stay older. The cells retained their intrinsic age nearly two decades after transplant. Their inherent steadiness suggests blood cells could be the master clock of human aging, as they are not easily influenced by their environment, Matsuyama said.

The study showed blood cells retain epigenetic patterns in DNA methylation — chemical groups attached to DNA — that can be used to calculate their age. Despite substantial age differences between donor and recipient (up to 49 years), the DNA methylation age of transplanted blood reflected the age of the donor, even after many years of exposure to the recipient’s body, researchers said.