Polyclonal Immunoglobulin E and Immunoglobulin G4 antibodies to Dactylis glomerata allergens (Anti-Dac g IgE/IgG4)

Polyclonal IgE and IgG4 antibodies to Dactylis glomerata (orchard grass) are key components of the adaptive immune response in individuals sensitized to grass pollen. Dactylis glomerata is a major source of aeroallergens, including Dac g 1 and Dac g 5, which trigger allergic rhinitis and asthma (Source: WHO/IUIS Allergen Nomenclature Database). IgE antibodies specific to these allergens bind to high-affinity FcεRI receptors on mast cells and basophils; upon subsequent allergen exposure, cross-linking occurs, leading to the release of inflammatory mediators (Source: Janeway's Immunobiology). In contrast, allergen-specific IgG4 antibodies, often induced during allergen immunotherapy (AIT), function as blocking antibodies by intercepting allergens before they can bind to cell-bound IgE, thereby promoting immune tolerance (Source: Akdis & Akdis, 2014, Journal of Allergy and Clinical Immunology). While these antibodies are primarily used as biomarkers to monitor the efficacy of AIT, the IgE component is also a therapeutic target for monoclonal antibodies like omalizumab, which sequesters free IgE to prevent allergic cascades (Source: FDA, Xolair Prescribing Information).

Other names

Orchard grass pollen antibodiesCocksfoot grass antibodiesAnti-Dac g IgE and IgG4Grass pollen specific antibodiesDactylis glomerata specific IgE and IgG4

Omalizumab binds to the Cε3 domain of the Fc region of free IgE, preventing its interaction with the high-affinity IgE receptor (FcεRI) on mast cells and basophils, which reduces the release of allergic mediators (Source: PubChem, CID 160786). Allergen immunotherapy (AIT) using Dactylis glomerata extracts works by inducing regulatory T cells (Tregs) and B cells, which produce IL-10 and TGF-beta, leading to a class switch from IgE to IgG4, effectively blocking IgE-mediated mast cell activation (Source: Shamji & Durham, 2017, Lancet).