Dec 25, 2025
3 min read
In an encouraging development, a team of researchers has successfully used a combination of three messenger RNAs (mRNAs) to replenish senescent T cells in mice, opening the door to new ways to boost immune systems in older people. The results were published in the journal Nature and presented at the annual meeting of the American Academy of Sciences.
In a promising breakthrough, a team of researchers was able to restore aging T cells in mice using a combination of three messenger RNAs (mRNAs), opening the door to new ways to boost the immune system in the elderly.The discovery, published in Nature and presented at the annual meeting of the American Society of Hematology, raises the prospect of improving the effectiveness of cancer vaccines and treatments for the aging population.
Decreased immunity due to aging
As we age, the immune system loses efficiency, and one major reason is the functional decline of T cells, which are responsible for coordinating the immune response and eliminating infected or cancerous cells.Not only do their numbers decrease, but so does their ability to respond appropriately to threats.This decline explains why vaccines are less effective in older people and why some immunotherapies do not produce the same results as in younger patients.
One of the most important biological processes in this process is the destruction of the thymus, the gland where T cells are produced. Over time, the thymus shrinks and is replaced by fatty tissue, which prevents the production of new cells.Although trying to change the problem with hormonal drugs and other drugs, the results are disappointing.
An indirect but effective strategy: targeting the liver
Faced with the difficulty of restoring the thymus, researchers led by Mirco Friedrich, from the German Cancer Research Center in Heidelberg, chose a less obvious route: instead of directly interfering with the thymus, they sent the treatment to the liver. The decision was based on physiological principles: blood loaded with T cells flows continuously through the liver, transforming this organ into a kind of cellular “service station” ideal for influencing these cells without disturbing their place of origin.
The therapy involves administering a cocktail of three different mRNAs twice a week, designed to activate molecular pathways that deteriorate with age.To develop this strategy, the researchers analyzed in detail how patterns of gene activity in T cells change from birth to 20 months in mice, a stage considered advanced for these animals.
Good results in immune response
After the treatment was applied, the aged mice showed a significant improvement in the immune response, both against vaccines and immunotherapy against cancer.The T cells have recovered part of their ability to recognize and attack pathogenic or malignant cells, a behavior more typical of young organisms.This functional recovery suggests that it is not necessary to completely replace the damaged cells, but instead it is possible to reactivate their dormant or switched off internal mechanisms.aging.
This discovery could have a major impact on the treatment of age-related diseases.One of the most important is the so-called "chronic low-grade inflammation", a state of chronic recovery that is associated with pathologies such as arteriosclerosis, Alzheimer's disease and some cancers.If T cells can be restored, this inflammation can always be reduced.
Future repercussions and care
Although the results in mice are encouraging, the leap to humans requires extensive validation.The person immune system is more complicated and is influenced by many external causes, from hose microbiota to lifestyle.However, the study paves the way for new therapeutic approaches based on MRA, a technology that has already shown its effectiveness in vaccines such as the for Covid-19.
A simple analogy can help us understand the implications of this research: If we imagine the immune system as an army, T cells are veterans who have been exhausted after years of war.mRNA therapy does not create new recruits, but allows these soldiers to regain energy, memory and sharpness.This, therapeutically, represents a bioeconomy of great value.
The applications can be broad: the best response to vaccinations in older patients, the most effective cancer treatment in older patients, and perhaps in the future preventative measures to reduce immune system aging.
