Posted by 
Aging impairs the immune system’s response to the flu virus in multiple ways, weakening resistance in older adults, researchers examined the innate immune response to the flu virus. They collected blood samples from healthy young adults and older adults.
They isolated monocytes, a type of white blood cell, from the samples and stimulated the monocytes with either flu virus or a mimic of the virus. The immune response in cells from older adults was severely impaired in critical ways, the researchers found.
To fight the flu virus, the body needs to activate potent antiviral proteins called interferons. But in older adults, this response is weakened by age-related damage to a molecule, TRAF3, that signals immune cells to make interferon. Without that signal, and another involving antiviral genes, resistance to flu falls short.
haleplushearty.blogspot.com