Newly found mechanism could pave way to end allergic reactions

Scientists have found a new mechanism in which an antibody can prevent allergic reactions in a broad range of patients.
The breakthrough could pave the way for a far more effective allergy medicine.
The antibody interacts in a complex biochemical process in the human body by which it prevents the human allergy antibody (IgE) from attaching to cells, thus keeping all allergic symptoms from occurring.
"We can now describe the interaction of this antibody with its target and the conformational changes very accurately," said Edzard Spillner, from the Aarhus University in the Denmark
"This allows us to understand, how it interferes with the IgE and its specific receptors on the immune cells of the body, which are responsible for releasing histamine in an allergic reaction," said Spillner.

Generally, an allergic person produces high levels of IgE molecules against external allergens when exposed to them.

These molecules circulate in the blood and are loaded onto the effector cells of the immune system which triggers the production of histamine and thereby an immediate allergic reaction in the body.
The function of the antibody is that it interferes with binding of IgE to the two specific effector (CD23 and FceRI) on the immune cells, thereby making it impossible for the allergy molecule to bind.
In the study, published in the journal Nature Communications, the researchers observed that the antibody also removes the IgE molecules even after binding to its receptors.

"Once the IgE on immune cells can be eliminated, it doesn't matter that the body produces millions of allergen- specific IgE molecules. When we can remove the trigger, the allergic reaction and symptoms will not occur," said Spillner.
The antibody is particularly interesting because it is effective, and at the same time considerably smaller than therapeutic antibodies currently used to produce allergy medicine.
"It is a so called single domain antibody which easily produced in processes using only microorganisms. It is also extremely stable, and this provides new opportunities for how the antibody can be administered to patients," said Spillner.