Major histocompatibility complex class II-T-cell receptor interface (Bet v 1) (MHC II-TCR (Bet v 1))

The Major histocompatibility complex class II-T-cell receptor interface (Bet v 1) is a specialized immune complex formed during the presentation of birch pollen allergens to the human immune system. It consists of a trimolecular assembly where a T-cell epitope derived from the Bet v 1 protein is bound within the peptide-binding groove of an MHC class II molecule (predominantly HLA-DR) and recognized by a specific T-cell receptor (TCR) on CD4+ T helper cells (Jahn-Schmid et al., 2005). This interaction is the fundamental step in the activation of Th2 cells, which drive the production of IgE and the subsequent allergic inflammatory cascade in sensitized individuals (Schirmer et al., 2005). As a therapeutic target, this interface is exploited in allergen-specific immunotherapy (ASIT) using synthetic peptides. These peptides are designed to bind MHC II and interact with the TCR to induce immunological tolerance or anergy without cross-linking IgE on mast cells, thereby treating the underlying cause of birch pollen allergy while minimizing the risk of anaphylaxis (Larche, 2007).

Other names

HLA-DR-Bet v 1-TCR complexMHC-peptide-TCR trimolecular complexBet v 1 T-cell epitope interfaceHLA-DRB1*01:01-Bet v 1 complex

Induction of peripheral T-cell tolerance, anergy, or the differentiation of regulatory T cells (Tregs) through modified antigen presentation and TCR signaling.