Major pollen allergen Amb a 1 (Amb a 1)

Major pollen allergen Amb a 1 is the primary protein responsible for ragweed-induced allergic rhinitis and asthma. It is a pectate lyase enzyme produced by short ragweed (Ambrosia artemisiifolia) that facilitates pollen tube penetration of the stigma by degrading pectin in the plant cell wall (UniProt P08029). In sensitized individuals, Amb a 1 triggers a Type I hypersensitivity reaction by cross-linking IgE on the surface of mast cells and basophils, leading to the release of inflammatory mediators (PubMed 25151914). The protein is typically processed into alpha and beta chains, which contain the major T-cell and B-cell epitopes (WHO/IUIS Allergen Nomenclature). Therapeutic strategies targeting Amb a 1 primarily involve allergen-specific immunotherapy (ASIT), which aims to desensitize the immune system through controlled exposure (FDA Ragwitek). This process promotes the production of protective IgG4 antibodies and the induction of regulatory T cells, effectively modifying the underlying disease rather than just treating symptoms.

Other names

Pectate lyase Amb a 1Ambrosia artemisiifolia allergen 1Antigen EAgE

Allergen-specific immunotherapy (ASIT) involves the repeated administration of the allergen to induce immunological tolerance, shifting the immune response from a Th2-mediated allergic response to a Th1/Treg-mediated response, increasing allergen-specific IgG4 levels, and reducing IgE-mediated mast cell degranulation.