NEW YORK July, 16, 2008 When it comes to allergies, both the problem and the solution are found within us. Our immune systems respond to foreign substances with an arsenal of cells. Some are programmed to "remember" invaders they've encountered in the past. Normally, anything previously identified as harmless is allowed to pass. Sometimes, however, the immune response goes awry, triggering an allergic reaction.
Now, researchers at NYU School of Medicine have zeroed in on a class of custom-made immune cells that block allergic reactions. These regulatory T cells are manufactured according to instructions from a gene called Foxp3 whenever we eat or inhale a potential allergen for the first time, ensuring that the next time we encounter that substance, we will not mount an allergic response.
"We don't become allergic to lots of thingswe eat all kinds of things, we breathe all kinds of things, and what prevents us from developing allergies is that we make regulatory T cells, which specifically recognize this allergen," says Maria A. Curotto de Lafaille, Ph.D., Associate Research Scientist at NYU Langone Medical Center. "Every time we don't react to something or don't become allergic, it's not because nothing is happening," Dr. de Lafaille explains. "It's because something very important is happening: We're making these cells,"
Mucosal tissue, which lines both the respiratory and digestive tracts, has long been known as an effective barrier against allergens, which are always protein molecules. The NYU research shows that Foxp3-directed regulatory T cells (Treg) are produced in the mucosal tissue and remain there to prevent allergic reactions. New ones are tailor-made every time an unknown protein is inhaled or ingested. The inability to make Treg cells results in high susceptibility to becoming allergic.
The NYU researchers induced allergic reactions in mice with a Foxp3 mutation that prevented formation of Treg cells. Exp
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| Contact: Lorinda Klein lorindaann.klein@nyumc.org NYU Langone Medical Center / New York University School of Medicine Source:Eurekalert |