Researchers at the Trudeau Institute say that a previously-unknown messaging mechanism within the human immune system prompts specific influenza-fighting cells to the lung airways during an infection.
Researchers have known for some time that white blood cells congregating in the lung and directly attacking the virus play an important role in defending against influenza, but it has never been clear how exactly these white blood cells know when they are required in the lung.
Now, the new study offers important insights into the navigational aids used by these cells as they maneuver through the human body.
Researchers, led by Dr. David Woodland, have shown that lungs, which have been infected with the influenza virus, produce a series of chemicals, or chemokines, which act as beacons for specific types of white blood cells.
While circulating in the bloodstream, these white blood cells recognize the chemical messages signaling the presence of the virus and the need for them to move into lung tissues.
"An important aspect of these findings is that this response occurs early in the disease process, typically within a couple of days of the initial infection.
"It also turns out that only a fraction of the available white blood cells are capable of recognizing these chemokine messages.
"Discovering that this response occurs rapidly, and that only a specific subset of white blood cells can recognize these messages, helps provide important new information for researchers working towards developing better a better influenza vaccine," Dr. Woodland, director of the Trudeau Institute, said.
The study is published in the scientific journal Immunity.