Human Immunoglobulin G specific for Poa annua pollen allergens (Poa a-specific IgG)

Human Immunoglobulin G (IgG) antibodies specific for Poa annua (Annual Bluegrass) pollen allergens are a specialized subset of antibodies that play a protective role in allergic diseases. In sensitized individuals, these antibodies—especially the IgG4 subclass—act as blocking antibodies by binding to major allergens such as Poa a 1 and Poa a 5 (WHO/IUIS Allergen Nomenclature). This binding effectively sequesters the allergens, preventing them from cross-linking IgE on the surface of mast cells and basophils, which would otherwise trigger the release of inflammatory mediators like histamine (Akdis & Akdis, 2014). The production of these specific IgG antibodies is a primary therapeutic goal of allergen-specific immunotherapy (AIT), a treatment involving the gradual administration of Poa annua pollen extracts to induce immune tolerance. Consequently, the measurement of these antibodies serves as a vital biomarker for assessing the immunological shift and clinical efficacy of desensitization therapies (Shamji & Durham, 2017). While not a drug target in the traditional sense, they are the functional mediators of the clinical benefit observed in grass pollen allergy treatments.

Other names

Anti-Poa annua IgGPoa a-specific IgG4Annual Bluegrass pollen-specific IgGBlocking antibodies for Poa annua

Allergen immunotherapy induces the production of allergen-specific IgG antibodies, particularly the IgG4 subclass, which act as blocking antibodies. These antibodies compete with allergen-specific IgE for binding to pollen allergens, thereby preventing the cross-linking of IgE on mast cells and basophils and the subsequent release of inflammatory mediators (Akdis, M., & Akdis, C. A. (2014). Mechanisms of allergen-specific immunotherapy. Journal of Allergy and Clinical Immunology).