Canada Research Chair in Aging and Immunity
Tier 2 - 2014-09-01
Department of Pathology and Molecular Medicine Profile | Bowdish Lab - Macrophage Biology at McMaster
Discovering why our immune system changes with age and how this predisposes us to respiratory infections.
This goal of this research is to improve immune function in older adults as a novel preventative and therapeutic strategy for respiratory infections.
Fighting Infection in the Elderly
Upper respiratory tract infections, such as pneumonia and influenza, are a leading cause of deaths among the elderly and a precipitating factor in their declining health. The efficacy of the most common treatment – antibiotics – could be more effective if we combined it with immune modulating drugs to combat some of the changes to the aging immune system.
Dawn Bowdish, an associate professor of Pathology and Molecular Medicine, leads an ambitious and innovative research program that is questioning longstanding assumptions about the aging immune system.
One of those assumptions is that old people get sick because their immune systems don’t work. Not true, says Bowdish. They just work differently.
It is widely known that as we age we become more inflamed. Bowdish found that the higher levels of inflammation in 2 year old mice (about the same as a 75 year old person) caused some types of white blood cells to enter the bloodstream before they were fully mature and produce even more inflammation.
While small amounts of inflammation are required to fight infections like pneumonia, the old mice produced so much that their white blood cells were less effective. Reducing levels of inflammation helped them to clear the infection and get better.
This may help explain why older adults with pneumonia do better when given corticosteroids, to reduce inflammation in addition to antibiotics. It may also reveal why chronic inflammatory diseases such as diabetes, cardiovascular disease, and dementia – all characterized by having elevated levels of pro-inflammatory cytokines – carry an increased risk for acquiring pneumonia.
Understanding the interplay between age, inflammation and anti-bacterial impairment could lead to the development of preventative and therapeutic strategies that will keep us all living longer and healthier.