A study published by the Barcelona Supercomputing Center – Centro Nacional de Supercomputación (BSC-CNS) in Nature Aging on Apr. 11 shows that the immune system ages differently in men and women, identifying specific cells and genes involved in this process.
The findings are important because they provide a molecular explanation for why men are more prone to infections and cancers, while women tend to have stronger immune responses but also higher rates of autoimmune diseases. Understanding these differences is key as people age, since changes in the immune system can increase susceptibility to various diseases.
Researchers analyzed blood samples from nearly 1,000 adults of different ages using single-cell RNA sequencing technology. This allowed them to study over one million blood cells and observe how gene activity shifts with age. The results indicate that women experience more pronounced changes in their immune systems as they get older, particularly an increase in inflammatory immune cells. This could help explain why autoimmune diseases are more common among women, especially after menopause.
In contrast, aging-related changes in men's immune systems were less extensive overall but included an increase in certain blood cells with pre-leukemia alterations. This may account for the higher frequency of some blood cancers among older men.
Marta Melé, leader of the Transcriptomics and Functional Genomics group at BSC and director of the study, said: "Many studies still do not take sex into account in their analyses, or directly only use data from men, so they leave key questions unanswered. Our research was born precisely from this need and combines a scientific outlook with a sex perspective, inclusive data, and great computational power." Aida Ripoll-Cladellas, researcher at BSC and first co-author of the study added: "The immune system plays a fundamental role throughout the organism; therefore, the differences we observed have a very important generalized impact on the entire body. Better understanding the aging of the immune system can help us understand processes that go beyond the blood and affect multiple tissues."
The authors conclude that treating aging as a uniform process overlooks critical biological differences between sexes. They suggest that recognizing these variations will be essential for improving immune health strategies tailored for both women and men.
