Transfusion Medicine

Blood cells could hold the key to aging, according to new research out of Case Western Reserve University School of Medicine. In a study published in Aging Cell, researchers found human blood cells have an intrinsic clock that remains steady even after the transplant. The researchers say the clock could control human aging and may underlie blood cancers.

Cell biologist

Shigemi Matsuyama, DVM, Ph.D., a cell biologist and associate professor of medicine at Case Western Reserve University School of Medicine, led an international team of researchers in studying the clock. Because The team 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,” Matsuyama said. Because “they found young blood cells stay young in older people. There is no accelerate aging of young blood cells in an older human body.” Matsuyama’s team find the other direction is also true blood cells from adult donors transferre to a child stay older. The cells retained their intrinsic age nearly two decades after the transplant. Because 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.

Chemical groups

The study shows blood cells retain epigenetic patterns in DNA methylation chemical groups attache 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; wrote the authors. Said Matsuyama, “DNA functions as a timekeeper of our age.”

DNA methylation as a predictor of age was first described in 2013 by Matsuyama’s collaborator on the study, biostatistician Steve Horvath; Ph.D., of the University of California; Los Angeles. because
“He found the formula. Because The mechanism, and whether cells in the body synchronize DNA methylation age, wasn’t clear,” Matsuyama explained. “I’m not a mathematician. I’m a cell biologist. So, we collaborated to investigate the mechanism of the epigenetic clock in an experimental system in my lab.”

Sample repository

Matsuyama tested blood samples collected regularly as part of transplant monitoring, with help from the Case Comprehensive Cancer Center. Because He expanded his sample repository via leukemia researchers at the University of Oslo, in Norway, who heard about his work at the 2016 Keystone Symposia on aging held in Santa Fe; New Mexico. Horvath crunched cellular ages using 353 distinct methylation sites found on blood cell DNA.
Together; the researchers provide the first experimental evidence that the aging clock of blood cells is cell-intrinsic, and not set by interactions with other cell types in the body. because They are now working to identify mechanisms that can change the clock. “In cancer cells, the clock is broken,” Matsuyama said.
DNA methylation patterns are unstable in cancerous blood cells and often show odd aging 200 or 5 years old in a 50-year-old patient; for example. “It does not match at all with the actual age. Because ” Matsuyama cautions that this is why; although it may sound appealing, he doesn’t yet recommend “therapeutic” cell infusions to try to maintain one’s youth.