Phleum pratense pollen allergen (Phl p) (Phl p)

Phleum pratense pollen allergen refers to a group of proteins found in Timothy grass pollen that trigger IgE-mediated allergic reactions in sensitized individuals. These allergens, particularly the major allergens Phl p 1 and Phl p 5, are responsible for symptoms of seasonal allergic rhinitis (hay fever) and allergic asthma (Source: UniProt P43213, Q40240). In the immune system, these proteins bind to specific IgE antibodies on the surface of mast cells and basophils, leading to degranulation and the release of inflammatory mediators such as histamine and leukotrienes (Source: PubMed PMID: 25617731). Therapeutically, Phleum pratense allergens are used as the active ingredients in allergen-specific immunotherapy (AIT) to induce immune tolerance. Drugs like Grastek and Oralair utilize these allergens to shift the immune response from a pro-allergic Th2 profile to a regulatory T cell (Treg) and Th1 profile, increasing the production of blocking IgG4 antibodies (Source: FDA Label for Grastek). This treatment addresses the underlying cause of the allergy rather than just managing symptoms. It is one of the most well-characterized allergen groups used in clinical practice for desensitization (Source: PubMed PMID: 30143322).

Other names

Timothy grass pollen allergenPhleum pratense extractTimothy grass pollenPhl p allergens

Allergen-specific immunotherapy (AIT) induces immunological tolerance by promoting the expansion of regulatory T cells (Tregs) and B cells, shifting the cytokine profile from Th2 to Th1, and stimulating the production of allergen-specific IgG4 antibodies that block IgE-mediated mast cell activation (Source: PubMed PMID: 30143322; FDA Label for Grastek).