The term allergen is used to describe a substance that is detected as being foreign on making contact with the organism and brings about excessive defense on the part of the immune system, an allergic reaction. It has been known for a long time now that in the event of repeated contact with a very low dose of an allergen the body can develop a kind of immunity to it. This process is referred to as "low zone tolerance." The exact mechanisms on which this immunity is based are still largely unknown. The present study of german researchers was able to decipher important cellular mechanisms for the first time using a mouse model. Killer dendritic cells, which are also described as the sanitary police, release a certain semiochemical on making contact with an allergen. In cells that facilitate the allergic reaction this so-called tumor necrosis factor triggers programmed cell death, apoptosis. As a result, it is not possible for an allergic reaction to develop. The very different personal degrees of ability to develop this "low zone tolerance" are probably also the reason why some individuals react to certain allergens and others do not.
"The results of the study are basically of relevance to everyone," says Professor Marcus Maurer from the Charité Allergy Center. "Especially people who have greater contact with allergenic substances run the risk of developing an allergy some day." They include, for example, people employed in hair salons and in the jewelry and fashion industries, but also hospital staff. "In our research paper we identified the mechanism on which the prevention of an allergy is based," Maurer explains. The dermatologist and allergist assumes that the results can in future be used in therapy and therefore to avoid allergies.
MEDICA.de; Source: Charité Universitätsmedizin Berlin