Scientists from Spain, published research in the journal Nature, have found that as humans age, their hematopoietic system loses its variety and becomes more vulnerable. By the age of 50, most people have only a few dominant stem cells in their blood, displacing the rest of the competitors. These dominant clones mainly produce myeloid cells associated with chronic inflammation, a phenomenon known as “inflammatory aging.”
The researchers used epigenetic marks to trace the activity of stem cells with age and developed a new technology called EPI-CLONE to analyze blood genealogy. The results showed that in older mice, up to 70% of blood cells originated from a few dozen clones. Similarly, by age 60, the dominance of large clones in humans becomes almost inevitable, even without famous cancer mutations.
This age-related clonality could be a normal part of aging, according to experts. The EPI-CLONE technology offers the potential for early diagnosis of blood aging and rejuvenation methods. Suppressing specific clones that cause inflammation could restore youthful hematopoiesis and enhance immune protection.
Lars Felten, a co-author of the research from the center of genomic regulation in Barcelona, explained that in youth, stem cells in the blood compete, providing diversity and stability. However, as people age, only a few dominant cells remain, reducing flexibility and making the system more vulnerable.
The study, a collaboration between CRG and the Institute of Biomedical Studies in Barcelona, aims to adapt EPI-CLONE for large-scale clinical trials to further explore its potential applications.