Lolium perenne pollen allergen (Lol p)

Lolium perenne pollen allergens, primarily Lol p 1 and Lol p 5, are the molecular triggers for Type I hypersensitivity reactions in individuals sensitized to perennial ryegrass (PMID: 12642832). These proteins function as antigens that cross-link specific IgE antibodies on the surface of mast cells and basophils, initiating a hypersensitivity reaction and the release of inflammatory mediators like histamine (PMID: 15585361). In clinical practice, these allergens are the functional targets of allergen-specific immunotherapy (AIT), where standardized extracts of Lolium perenne are administered to patients to induce immunological tolerance (PMID: 24943124). The therapeutic mechanism involves a shift from a Th2-dominated immune response to a Th1 and regulatory T cell (Treg) response, accompanied by the production of allergen-specific IgG4 antibodies that act as "blocking" antibodies to prevent IgE-mediated activation (PMID: 28214150). Drugs interacting with this target include various grass pollen extracts and sublingual immunotherapy tablets like Oralair (FDA Label). Safety concerns primarily involve the risk of systemic allergic reactions, including anaphylaxis, which requires medical supervision during the initiation of treatment (PMID: 25617732).

Other names

Ryegrass pollen allergenLolium perenne extractLol p 1Lol p 5Perennial ryegrass allergen

Allergen-specific immunotherapy (AIT) induces immunological tolerance by shifting the immune response from a Th2-mediated IgE response to a Th1/Treg-mediated response, increasing the production of blocking IgG4 antibodies (PMID: 24943124).