Allergen-specific B-cell receptor for Parietaria judaica allergens (BCR-Par j)

Allergen-specific B-cell receptors (BCRs) for Parietaria judaica allergens are membrane-bound immunoglobulins on B lymphocytes that recognize specific epitopes of Parietaria judaica pollen proteins, primarily the major allergens Par j 1 and Par j 2 (UniProt: P0C0Y4, P0C0Y5). These receptors are central to the allergic immune response, as their engagement by allergens triggers B-cell activation, clonal expansion, and differentiation into plasma cells that secrete allergen-specific IgE (PubMed: 11149992). This process is a hallmark of Type I hypersensitivity, leading to conditions such as allergic rhinitis and bronchial asthma in sensitized individuals (StatPearls: Allergic Rhinitis). In the context of therapy, these BCRs are the functional targets of allergen-specific immunotherapy (AIT), which utilizes Parietaria extracts or recombinant allergens to induce immunological tolerance (PubMed: 10852376). AIT promotes a shift from a Th2-biased IgE response to a Th1/Treg-mediated response characterized by the production of blocking IgG4 antibodies and the expansion of regulatory B cells (PubMed: 21463111). This therapeutic approach aims to modify the underlying disease by desensitizing the B-cell repertoire to the offending allergens. Monitoring the frequency and isotype of these specific BCRs provides insights into the efficacy of immunotherapy and the patient's allergic status.

Other names

Parietaria judaica allergen-specific B-cell receptorPar j 1-specific B-cell receptorPar j 2-specific B-cell receptorPellitory-of-the-wall allergen-specific BCR

Induction of immune tolerance through allergen-specific immunotherapy (AIT), leading to B-cell isotype switching from IgE to IgG4 and the expansion of regulatory B cells (Bregs) (PubMed: 21463111).