Scientific discoveries about how the ages are hugely important. Over the years the composition of immune cells shifts and their protective functions weaken. That reduces resistance to disease. Until recently, though, we knew little about how sex influences this deep transformation.
A study from the Barcelona Supercomputing Center — the National Supercomputing Center (BSC-CNS) — has for the first time shown that immune unfolds differently in men and women. The team identified the cells and genes responsible for this process and found a molecular explanation for the sex differences.
The results, published in Nature Aging, showed that women experience more pronounced changes in their immune systems with age, accompanied by an increase in inflammatory immune cells. The team believes this finding will help explain why:
- autoimmune diseases develop more often in women than in men
- these illnesses are especially common among older women
- certain inflammatory conditions flare up after menopause.
Meanwhile, the age-related changes in men’s immune systems were generally less pronounced. But the team did notice an increase in a population of blood cells in men that showed pre-leukemic changes. That observation may help explain why some types of blood cancer are more common in older men.
What researchers discovered about how the immune system ages
Finding these patterns was possible thanks to analyses of blood samples from about 1,000 people of different ages. The samples were collected throughout the participants’ adult lives. Overall, the researchers analyzed the activity of 20,000 genes in more than a million blood cells. In the study, the scientists used an innovative RNA sequencing technology that allowed them to:
- profile the complete RNA content of individual cells
- track how the immune system changes with age
- detect clear sex differences in the results.
To process and analyze the huge set of samples, the scientists used advanced computational methods that had never before been applied to such complex datasets. The supercomputer MareNostrum 5 was a key tool.
“Until now, most studies analyzed the immune system using averaged data from many cells at once, which made it hard to detect aging effects. Thanks to single-cell analysis and a much larger sample, we were able to uncover these patterns and compare them between biological sexes.” María Sopena-Ríos, lead author of the study.
Why aging needs to be studied by sex
Although scientists had some idea that the immune system ages differently by sex, have generally been underrepresented in those studies. This is the first time researchers analyzed a large, balanced set of male and female samples.
“Many researchers have still not accounted for sex in their analyses or have used only data from , so key questions remained unanswered,” said Marta Mele, head of the transcriptomics and functional genomics group at BSC.
The study’s authors confirmed the need to include sex as a key variable in personalized medicine for aging. Finding sex-specific senescent cell types and biomarkers opens the door to developing preventive, diagnostic, and therapeutic strategies for both women and men. Those strategies could improve immune health and support healthier aging worldwide.
Photo: pixabay.com
