Timothy grass pollen allergen extract

Timothy grass pollen allergen extract is a therapeutic preparation derived from the pollen of Phleum pratense, containing a complex mixture of allergenic proteins such as Phl p 1 and Phl p 5 (Source: WHO/IUIS Allergen Nomenclature Database). It is primarily used in allergen-specific immunotherapy (AIT) to treat patients with grass pollen-induced allergic rhinitis and conjunctivitis (Source: FDA Label for Grastek). The extract functions by exposing the immune system to controlled, increasing doses of the allergen to induce immunological tolerance. This process involves the induction of regulatory T cells (Tregs) and the production of allergen-specific IgG4 antibodies, which compete with IgE for allergen binding (Source: Akdis & Akdis, 2014, Nature Reviews Immunology). By shifting the immune response from a Th2-biased allergic profile to a Th1/Treg profile, the extract reduces mast cell and basophil degranulation upon natural exposure (Source: Moingeon, 2013). Clinically, it provides long-term symptom relief and can prevent the development of asthma in allergic individuals (Source: Durham & Penagos, 2016). Notable safety concerns include the risk of local oral reactions and systemic anaphylaxis, requiring the first dose to be administered under medical supervision (Source: FDA Label for Grastek).

Other names

Phleum pratense pollen extractTimothy grass pollenPhl p extractGrass pollen allergen extract

Induction of allergen-specific regulatory T cells (Tregs) and B cells, leading to the production of IgG4 blocking antibodies and a shift from a Th2 to a Th1 immune response, which suppresses IgE-mediated mast cell and basophil activation (Source: Akdis & Akdis, 2014, Nature Reviews Immunology).