Like birds, ants, and other living organisms, immune cells work collectively to kill viruses like the flu. The finding offers new insights into how immune cells work together to get to their final destination, the site of an injury or infection.
The body is expansive and a virus or bacteria can take hold in any number of locations: the lungs, the throat, the skin, the stomach or the ear, just to name a few. How do immune cells, specifically the ones that are responsible for killing foreign invaders, know where to go?
Cells called neutrophils, the “first responders” of the immune system, are the key, researchers discovered. They arrive at the site of injury within an hour of infection and leave a chemical “trail” of sorts behind them.
Lost T Cells
Killer immune cells called T cells use this trail to find the site of injury and subsequently destroy the invader.
In fact, when scientists removed neutrophils (or their trails) from the equation, T cells didn’t find the site of injury as quickly or easily; they were more dispersed, fewer made it to the site of injury, and the ones that did were less effective at fighting the infection.
Minsoo Kim, lead author of the paper and associate professor of microbiology and immunology at the University of Rochester, says:
“Immune cells team up and share information to get their job done, much like many types of animals take part in collective behaviors to benefit the group as a whole.”
Designing Better Vaccines
David J. Topham, study coauthor and a professor of microbiology and immunology, adds:
“Understanding how immune cells collaborate to arrive at the site of an infection will lead to new ways to control and improve the body’s response to all types of illnesses.”
For example, in people with autoimmune disorders like multiple sclerosis and lupus, the immune system mistakenly attacks and destroys healthy body tissue. If scientists understood how to disrupt or stop immune cells’ movement to healthy tissue, they may be able to improve the quality of life of people living with these devastating diseases.
Similarly, recognizing how to boost the number of immune cells that travel to fight an infection could help scientists design better vaccines for viruses like the flu.
Neutrophil trails guide influenza-specific CD8+ T cells in the airways Kihong Lim, Young-Min Hyun, Kris Lambert-Emo, Tara Capece, Seyeon Bae, Richard Miller, David J. Topham, and Minsoo Kim Science 4 September 2015: 349 (6252), aaa4352 [DOI:10.1126/science.aaa4352]