Why are the elderly so vulnerable to pneumonia?
A study featured on the cover of the Journal of Immunology is providing insight into why the elderly are so vulnerable to pneumonia and other bacterial infections.
Compared with younger adults, the elderly are at higher risk of becoming seriously ill or dying from pneumonia. Moreover, vaccines against the disease are less effective in the elderly.
To help understand why, Loyola researchers examined two types of immune system cells, macrophages and B cells, located in specialized areas in the spleens of mice. Macrophages gobble up bacteria, while B cells produce antibodies that fight bacteria.
Macrophages and B cells appeared to be just as effective in old mice as they were in younger mice. But there were fewer of them.
“If we knew how to replenish these cells, we might be able to lower the risk of bacterial infections in the elderly,” said senior author Pamela Witte, a Professor in the Department of Microbiology and Immunology at Loyola University Chicago Stritch School of Medicine.
“This is an unexplored area in ageing.”
The finding also could provide clues to developing vaccines against pneumococcal pneumonia that would be more effective in the elderly, said first author Shirin Birjandi, who is completing her PhD at Loyola.
Researchers wrote that understanding changes such as these “is important for developing more efficient therapies for preventing diseases, such as bacterial pneumonia, that have shown to be highly detrimental in the elderly”.
