Hazelnut allergen protein (Cor a)

Hazelnut allergen proteins are a group of proteins from the hazelnut (Corylus avellana) that trigger IgE-mediated hypersensitivity reactions in sensitized individuals (WHO/IUIS Allergen Nomenclature, allergen.org). These proteins are classified into several distinct families based on their structure and biological function, including the heat-labile PR-10 proteins (e.g., Cor a 1), which are often associated with mild oral allergy syndrome due to cross-reactivity with birch pollen, and the heat-stable seed storage proteins such as 2S albumins (e.g., Cor a 14) and 11S globulins (e.g., Cor a 9) (UniProt, uniprot.org). Seed storage proteins and non-specific lipid transfer proteins (e.g., Cor a 8) are particularly significant as they are frequently linked to severe, systemic allergic reactions and anaphylaxis (PubMed, PMID: 21143415). In the context of biotechnology and clinical medicine, these proteins serve as the active components in allergen-specific immunotherapy (AIT), where they are used to induce immunological tolerance (NIH, ncbi.nlm.nih.gov). The therapeutic goal is to modulate the patient's immune system, promoting a shift from a Th2-biased allergic response to a state of clinical tolerance characterized by increased regulatory T-cell activity and the production of protective IgG4 antibodies (Journal of Allergy and Clinical Immunology, jacionline.org). Clinical management often utilizes component-resolved diagnostics to identify specific protein sensitivities and assess the risk of severe reactions. While no hazelnut-specific oral immunotherapy is currently FDA-approved, standardized extracts are used in diagnostic testing and investigational treatments.

Other names

Corylus avellana allergenFilbert allergenCor a proteinsCor a 1Cor a 8Cor a 9Cor a 11Cor a 14Hazelnut allergen

Induction of immunological tolerance via allergen-specific immunotherapy (AIT), which promotes a shift from Th2-mediated IgE responses to regulatory T-cell (Treg) activation and the production of protective IgG4 antibodies that compete with IgE for allergen binding.