Dectin-1: An Immune Receptor that Protects Against Asthma and Allergies
A receptor thought to trigger allergic reactions turns out to do the opposite.
Why do only some people develop allergies? Research conducted by Marsha Wills-Karp, PhD, suggests that the answer may lie in a mechanism that evolved to prevent them.
Wills-Karp, chair of Environmental Health and Engineering and Anna M. Baetjer Professor in Environmental Health, investigates the molecular basis of allergic airway diseases like asthma. In a study published in Science Immunology in February, she and her colleagues focused their attention on dectin-1, a receptor found in the cells lining the sinuses, throat and lungs.
Previous research suggested that dectin-1 might trigger an allergic response to dust mites, a common environmental allergen. But Wills-Karp’s team found that mice lacking dectin-1 were more sensitive to dust mites, indicating that the receptor inhibited rather than promoted an allergic reaction.
The scientists determined that dectin-1 recognizes a harmless protein present not only in dust mites, but also in shrimp and other allergy-inducing invertebrates. Once activated, the receptor puts the brakes on an immune response that might otherwise snowball into a full-blown allergic reaction.
“It’s a protective pathway, and if you lose it, you may be more susceptible to allergic disease and asthma,” Wills-Karp says.
In fact, the researchers found that adults with asthma triggered by dust mite sensitivity had abnormally low levels of the receptor. And children with asthma were much more likely to have a genetic mutation that suppressed their production of dectin-1.
These findings could lead to new treatments for allergies and asthma. Wills-Karp also suspects that other receptors might inhibit allergic reactions to pollens, hinting at the possibility of novel therapies for seasonal allergies, as well.