Short ragweed pollen allergen Amb a 9 and Amb a 10 (Amb a 9/10)

Amb a 9 and Amb a 10 are calcium-binding proteins, specifically polcalcins, found in the pollen of Ambrosia artemisiifolia (short ragweed). They are classified as minor allergens and pan-allergens due to their high degree of cross-reactivity with polcalcins from other plant species, such as mugwort, birch, and olive. In sensitized individuals, these proteins trigger Type I hypersensitivity reactions by binding to IgE on the surface of mast cells and basophils, leading to the release of inflammatory mediators like histamine. Clinically, they contribute to symptoms of allergic rhinitis and asthma during the ragweed pollination season. While Amb a 1 is the primary focus of ragweed allergy management, Amb a 9 and 10 are important for component-resolved diagnosis to identify patients with broad cross-reactivity. They are present in therapeutic ragweed pollen extracts used in allergen-specific immunotherapy (AIT), which aims to desensitize the immune system and induce long-term tolerance by shifting the immune response from a Th2-mediated profile to a Treg/Th1-mediated profile.

Other names

PolcalcinCalcium-binding protein from short ragweedRagweed pan-allergenAmb a 9.0101Amb a 10.0101

Allergen-specific immunotherapy (AIT) induces immune tolerance by shifting the immune response from a Th2-mediated allergic profile to a Treg/Th1-mediated profile, increasing the production of IgG4 blocking antibodies and reducing IgE-mediated mast cell degranulation.