Very recently, researchers discovered an important population of immune cells called memory T cells living in parts of the body that interact with the environment such as skin, lung, and GI tract. How these "resident" memory T cells are generated was unknown, and their importance with regard to how our immune system remembers infection and how it prevents re-infection is an area of intense research.
Thomas S. Kupper. Image courtesy of Brigham and Women's Hospital
Now, a study by a Brigham and Women's Hospital (BWH) research team led by Xiaodong Jiang, a research in dermatology, and Thomas S. Kupper, Chair of the BWH Department of Dermatology and the Thomas B. Fitzpatrick Professor of Dermatology at Harvard Medical School, has used a model involving a vaccinia virus infection of the skin to answer important questions about how these newly discovered cells protect us.
The study was published online in February 29, 2012 in Nature.
Jiang and Kupper used skin infection with vaccinia virus to study the relative roles of central memory T cells (T cells that circulate in the bloodstream) and resident memory T cells in protective immunity. They found that after infection, disease-specific T cells were rapidly recruited not only to the infected site, but also to all areas of skin.
They further showed that multiple additional infections at future time points led to an accumulation of even more of these resident memory T cells in the skin, and that these cells remained in the skin for long periods of time.
Finally, Jiang and Kupper showed, for the first time, that resident memory T cells were the most important protective immune cells in fighting infection-much more important than central memory T cells, which were ineffective at rapid immune protection by themselves.
"This work suggests a fundamental reassessment of how vaccines are both constructed and delivered," said Kupper. "These results have altered the way we think about the immune system and vaccination for infectious diseases."
Adapted from Brigham and Women's Hospital press release.
