Birch pollen allergen peptide–MHC class II complex (Bet v 1-pMHC II)

The birch pollen allergen peptide–MHC class II complex is a molecular assembly formed by the binding of a processed peptide from the major birch allergen, Bet v 1 (UniProt P15494), into the peptide-binding groove of a Major Histocompatibility Complex (MHC) class II molecule, most commonly HLA-DRB1*01:01 (PubMed: 23434283). This complex is displayed on the surface of professional antigen-presenting cells and serves as the primary ligand for allergen-specific CD4+ T-cell receptors (TCRs). In sensitized individuals, the recognition of these complexes by Th2 cells drives the allergic cascade, including IgE production and airway inflammation (PubMed: 15191563). This complex is a central target for allergen-specific immunotherapy (AIT), which seeks to induce immunological tolerance by modulating the T-cell response (PubMed: 28213450). Therapeutic approaches include the use of peptide-based vaccines designed to target these complexes without cross-linking IgE on mast cells, thereby reducing the risk of anaphylaxis. Additionally, synthetic versions of these complexes, such as MHC-peptide tetramers, are used as diagnostic biomarkers to monitor the efficacy of immunotherapy by quantifying changes in the allergen-specific T-cell population (PubMed: 25544250).

Other names

Bet v 1 peptide-HLA-DR complexBirch pollen allergen pMHCMajor birch pollen allergen peptide-MHC class II complexBet v 1:HLA-DRB1*01:01 complex

Induction of immunological tolerance through the modulation of allergen-specific CD4+ T cells, involving mechanisms such as T-cell anergy, clonal deletion, or the induction of regulatory T cells (Tregs) that secrete IL-10 and TGF-beta (PubMed: 28213450).