Age a non-factor when it comes to virus immunity
Jonathan Bramson, a professor of Pathology and Molecular Medicine at McMaster, says the elderly are 'certainly capable' of developing immunity to viruses. The study was published Thursday in PLOS Pathogens.
Our immune system does not shut down with age, says a new study led by McMaster researchers.
The study was published Thursday in PLOS Pathogens, and shows that a specialized class of immune cells, known as T cells, can respond to viral infections in an older person with the same vigour as T cells from a young person.
“For a long time, it was thought the elderly were at a higher risk of infections because they lacked these immune cells, but that simply isn’t the case,” says Jonathan Bramson, the study’s principal investigator and a professor of Pathology and Molecular Medicine. “The elderly are certainly capable of developing immunity to viruses.”
Researchers at McMaster, the University of Toronto and the University of Pennsylvania examined a variety of individuals (younger than 40, between 41 to 59 years of age and older than 60) infected with three different viruses, including West Nile. They found the older group demonstrated perfectly normal immune responses.
Furthermore, the number of virus-fighting T cells and the functionality of the T cells were equivalent in all three groups.
“As we age, our bodies are still able to respond to new viruses, while keeping us immune to viruses we’ve been exposed to in the past,” Bramson says.
The results have important implications for vaccination of elderly individuals. Currently, vaccines for the elderly aren’t designed to elicit responses from these immune cells, and this might explain the lack of effective protection from the flu vaccine, explains Bramson. Vaccines specifically designed to generate T cell immunity may be more effective at protecting older adults.
The research was funded by the Canadian Institutes for Health Research and the U.S. National Institutes of Health. PLOS Pathogens is an open-access, peer-reviewed journal of the Public Library of Science.
