A new study has revealed why some people live beyond the age of 100. They analysed the data collected in previous studies to propose a new theory. Researchers from Boston University and Tufts Medical Centre said that people who live to be 100 years old or beyond that may have a unique composition of immune cells that keep them protected against illnesses. The study has been published in the peer-reviewed journal Lancet eBiomedicine. Previous studies have said that the proper functioning of immune system declines as age increases.
To arrive at the results, researchers performed single cell sequencing to assess molecules in peripheral blood mononuclear cells from seven people above the age of 100. These cells represent the type of immune cells circulating in the blood.
Immune cells help develop mechanisms in the body to help recover it from disease, which helps in promoting longevity.
"Our data support the hypothesis that centenarians have protective factors that enable them to recover from disease and reach extreme old ages," lead author Tanya Karagiannis, from the Tufts Medical Centre, was quoted as saying by USA Today.
The experts said the immune system's ability to respond to infections declines with age, but claimed this may be different in case of those who live beyond the age of 100.
"The findings provide support to the hypothesis that centenarians are enriched with protective factors that increase their ability to recover from infections," said senior author Paola Sebastiani, also from Tufts Medical Centre.
However, they were not able to find if the unique immunological ability is genetic, naturally occurring or a confluence of outside factors.
