Scientists have long known that the immune system plays an important role in aging. As people age, their response to vaccinations decreases, their risk of infection increases, and their levels of inflammation increase. A new study led by researchers at UCLA Health used routine laboratory test results to measure not only immune reactivity but how it directly relates to long-term mortality in patients.
why is it important
The results were announced on April 27th. Gero science It gives researchers a tool to study immune function in large patient populations using a tuberculosis screening test called the interferon gamma release assay (IGRA), a laboratory test that doctors already use regularly. The method the researchers used could indicate how well the immune system, particularly the adaptive immune system, which includes T cells, can respond to different threats.
what happened in the research
Researchers analyzed records (with personal information removed) of more than 16,000 people in the VA Greater Los Angeles Healthcare System who had negative or indeterminate IGRA tests. And they didn’t actually look at the patient’s tuberculosis results. Instead, they analyzed the results of control data. The main purpose of the control mechanism is to ensure that the tuberculosis test is effective by exposing the patient’s blood to phytohemagglutinin (PHA). PHAs typically elicit a strong immune response and may reveal a patient’s baseline immune performance.
what they found
The researchers correlated these control results with patient survival after excluding people with other illnesses. They found that patients with low immune responses had a 10 percent higher mortality rate over five years. This association remained even after accounting for age and chronic disease.
What this means for patients
Broadly speaking, the results provide doctors with a measure to predict a patient’s mortality based on their immune response, and could one day serve as a prognostic marker for common medical conditions. Another potential use is for patients seeking organ transplants. These tests are routinely done on people being considered for transplants and can help predict transplant outcomes and may also help doctors fine-tune the immunosuppression they administer. The same information could also be useful for cancer patients receiving immunotherapy.
what’s next
To turn this into a clinical tool, research is needed to link these test results to different health outcomes and other types of patients. Research is also needed to understand what tests reveal about the immune system itself. The stimuli used in the test affect T cells broadly, unlike the response to specific viruses or bacteria, so it’s important to know what’s happening downstream. Researchers also want to know the specific mechanisms that cause death, apart from correlations with age and frailty.
sauce:
University of California, Los Angeles Health Sciences
Reference magazines:
DOI: 10.1007/s11357-026-02221-y. https://link.springer.com/article/10.1007/s11357-026-02221-y
