A new inhibitory receptor expressed by mast cells ― specialized immune cells ― that suppresses severe allergic reactions is reported this week in Nature Immunology.
Allergens, insect venoms and some drugs can trigger a severe immune response called anaphylaxis, which can be life-threatening in susceptible individuals. This response occurs rapidly upon contact with the offending toxin and is mediated by specialized antibodies called IgE and mast cells. Allergen-IgE complexes trigger mast cell degranulation ― the process that releases histamines and other noxious substances underlying the allergic response.
Akira Shibuya and colleagues identify a new receptor called Allergin-1 that is expressed on mast cells. Allergin-1 blocks mast cell degranulation by deactivating the IgE receptor on these cells. Mice lacking allergin-1 display more severe anaphylactic responses.
Humans also express allergin-1, prompting the possibility that it might be harnessed to control severe allergy. However, further work is needed to understand how allergin-1 itself is activated.