Polyclonal IgE, IgG, and T-cell receptors specific for Alternaria alternata allergens

Polyclonal IgE, IgG, and T-cell receptors specific for Alternaria alternata allergens represent the collective adaptive immune components that recognize fungal proteins from the mold Alternaria alternata. This fungus is a major environmental allergen strongly associated with the development of severe asthma and allergic rhinitis (Gabriel et al., 2016, PMID: 26815475). In sensitized individuals, Alternaria-specific IgE binds to mast cells, triggering Type I hypersensitivity upon exposure to the major allergen Alt a 1. Therapeutic strategies like allergen immunotherapy (AIT) aim to modulate this system by inducing Alternaria-specific IgG4, which acts as a blocking antibody to prevent IgE-mediated activation (Bozek et al., 2017, PMID: 28453495). Additionally, T-cell receptors on specific CD4+ T-cells are targeted by AIT to shift the immune profile from a pro-inflammatory Th2 response toward a regulatory T-cell (Treg) phenotype. Monoclonal antibodies such as omalizumab also interact with this system by sequestering free IgE, thereby reducing the allergic cascade (FDA, Xolair Prescribing Information). This composite target is central to the pathophysiology of fungal-induced respiratory allergies and is the primary focus of both diagnostic testing and desensitization protocols.

Other names

Alternaria-specific antibodies and TCRsAlternaria-specific immune response componentsAnti-Alternaria alternata immunoglobulinsAlternaria-reactive T-cell receptors

Allergen immunotherapy (AIT) induces immune tolerance by promoting the production of Alternaria-specific IgG4 (blocking antibodies) and regulatory T-cells (Tregs), which suppress the Th2-mediated allergic response. Anti-IgE monoclonal antibodies, such as omalizumab, bind to the Fc region of free IgE, preventing it from binding to the high-affinity IgE receptor (FcεRI) on mast cells and basophils, thereby inhibiting the release of inflammatory mediators.