Scientists have discovered something remarkable about T cells, a type of immune cell.
These cells seem to have their own unique way of aging, different from other cells in our bodies.
Researchers at St. Jude Children’s Research Hospital and the University of Minnesota found that T cells can live through multiple lifetimes of an organism, even outliving the body they came from.
Their findings were published in Nature Aging.
Most cells in our bodies age and become less effective over time. However, T cells can keep dividing and multiplying without showing signs of aging.
This unique ability allows them to respond to infections and diseases throughout a person’s life.
The researchers found that healthy T cells’ age is not linked to the organism’s chronological age, meaning they don’t age the same way we do.
In their study, the scientists looked at T cells from pediatric patients with T cell acute lymphoblastic leukemia (T-ALL).
They discovered that these cancerous T cells appeared to be up to 200 years old, much older than the patients themselves. This rapid aging is likely due to the cancerous cells’ fast and continuous division.
To understand T cell aging better, the researchers used specific biomarkers called epigenetic markers. These markers accumulate over time and provide a way to measure a cell’s age, similar to counting tree rings. They found that T cells’ epigenetic clocks keep ticking, regardless of the organism’s lifespan.
Dr. Ben Youngblood from St. Jude explained, “The immune system needs to rapidly respond to threats like pathogens or tumors. In some cases, such as chronic viral infections, T cells must keep proliferating. This constant division could lead to cancer, but T cells have a unique way to avoid this.”
Through a collaboration with Dr. David Masopust at the University of Minnesota, the researchers used a model to study T cells across multiple mouse lifespans. They observed that the T cells didn’t decline over time but kept going, showing that their epigenetic clock was not bound by the organism’s life.
The researchers also studied T cells from patients with T-ALL. Dr. Caitlin Zebley from St. Jude said, “If T cells aged like their hosts, we would expect young T cells in pediatric patients. However, our findings showed these T cells to be very old, up to 200 years, due to rapid proliferation.”
This discovery helps scientists understand the aging process of leukemia cells. They were able to differentiate between normal aging processes and those unique to leukemia, providing insights into how T cells can avoid becoming cancerous despite their high proliferation rates.
Dr. Youngblood emphasized the importance of T cell survival for our overall health. “T cells have many chances to become cancerous, but they usually don’t. Otherwise, humanity wouldn’t survive.”
The ongoing research by Youngblood, Zebley, and Masopust aims to understand the mechanisms that prevent T cells from turning malignant. This work could lead to potential therapies that could halt or even reverse age-related impairments, offering hope for new treatments in the future.
If you care about health, please read studies about how Mediterranean diet could protect your brain health, and the best time to take vitamins to prevent heart disease.
For more health information, please see recent studies that olive oil may help you live longer, and vitamin D could help lower the risk of autoimmune diseases.
