A landmark study due to start in the coming months aims to test a method for rejuvenating our immune system in older age. The Phase 1 trial will target senescent T cells, which accumulate as we age or fight chronic disease and become less good at protecting us from illness.
“This trial is an important step towards testing whether we can safely rejuvenate exhausted immune cells and restore aspects of healthy immune function," says Dr Alessio Lanna from University College London (UCL) Medicine. "Our goal is to help establish immune rejuvenation as a new way of treating diseases linked to immune aging and dysfunction.”
The trial will administer this new experimental therapy to a cohort of adult participants who meet the study's criteria. The drug, developed by a biotechnology company founded by Dr Lanna named Sentcell, aims to revive tired, exhausted immune cells so they function as well in older bodies as in younger ones.
The therapy works to restore the immune system's innate ability to effectively recognize and respond to legitimate threats in the body.
The first in-human clinical trial will assess the drug's safety profile, hopefully providing a green light for further efficacy studies.
The drug will be administered via intramuscular injection, much like many vaccines. Once in the body, it's designed to reprogram the pathways that lead to immune dysfunction. Ideally, this will help the immune cells act like they're young again.
Ultimately, the goal is to provide the best setting for healthy aging at a molecular level.
"People living with HIV are now able to live long and healthy lives thanks to major advances in treatment, but many still experience features of accelerated immune aging," says Dr Lanna. "Similar patterns of immune dysfunction are also seen in cancer and other chronic diseases."
The trial comes after extensive research and a growing body of evidence indicating that some exhausted T cells can regain their former function. The focus here is on CD4+T cells, seen as the "conductors" of the immune system, organizing how the immune system responds to infection, cancer and disease.
Previous studies have found that rejuvenated CD4+T cells may also release telomere-containing structures – which researchers call "telomere rivers" – into the bloodstream. Telomeres, which sit at the ends of chromosomes to protect genetic material, shorten with age and are a reliable marker of biological aging.
Scientists are now looking at whether rejuvenated immune cells play a role in telomere protection and preserve the health of other tissues throughout the body, beyond the targeted T cells. This is yet to be demonstrated in humans.
The Phase 1 trial will recruit adult participants with evidence of immune dysfunction, including immune aging and chronic viral infection.
If successful, the experimental therapy could deliver an immune rejuvenation breakthrough – one that bolsters the immune system rather than targeting a specific pathogen or disease.
Researchers believe there's incredible potential in this approach to treating chronic infections, autoimmune disease and cancer, while also providing a novel therapy to prolong our health in older age.
Source: University College London
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