A team of researchers from Boston University School of Medicine and Tufts University studied the immune systems of seven volunteers ages 100 to 119. They discovered that these centenarians possess a unique immunity that appears to contribute to their impressive longevity.
Lead author Paola Sebastiani says the immune profiles of these long-lived people reflect both prolonged exposure to infections and an ability to recover from them.
What Does This Mean?
It may seem counterintuitive, but the researchers think long life is linked to many successful battles against disease, especially infections. The study participants — whose DNA the team analyzed — had a high number of certain immune cells with a distinct composition and activity that helped them fight disease effectively.
Sebastiani said the team identified protective factors in the centenarians that helped these people overcome various illnesses.
To reach this conclusion, the team sequenced peripheral blood mononuclear cells (PBMCs) — immune cells that originate in the bone marrow and circulate in the blood. The researchers compared those cells with samples from younger people who did not have centenarians in their family history. They observed significant shifts in the centenarians’ immune cell composition. The results suggested that the centenarians’ immune systems had endured decades of exposure to natural and environmental infections. Not only had the centenarians survived those infections, but their immune systems had also mounted robust responses.
The report says centenarians have a unique, highly functional immune system. It has successfully adapted to infections and recovers quickly. That resilience isn’t everlasting, the Daily Mail reported. However, the centenarians’ ability to recover declines much more slowly than it does in people who don’t reach 100.
The researchers cannot yet say whether the findings reflect a hereditary predisposition for exceptional longevity or simply the effects of immune systems hardened by decades of infections.
Looking ahead, Sebastiani said the team will study not only centenarians but also their descendants. She expects many of those descendants will also live to 100. That makes the immune cells of younger generations particularly important to study. Sebastiani hopes the team will soon gain a clearer picture of which inherited mechanisms slow aging.
