T-cell receptor recognizing Amb a 1–derived peptide–MHC class II complexes (TCR-Amb a 1-pMHCII)

The T-cell receptor (TCR) recognizing Amb a 1–derived peptide–MHC class II complexes is a pivotal molecular assembly in the development of ragweed pollen allergy. Amb a 1, a pectate lyase from Ambrosia artemisiifolia, is the immunodominant allergen responsible for most ragweed-induced Type I hypersensitivity reactions (Wopfner et al., 2005). When Amb a 1 peptides are presented by MHC class II molecules, specifically HLA-DR alleles, they are recognized by specific TCRs on CD4+ T cells, initiating a Th2-biased immune response (Jutel et al., 2016). This recognition leads to the secretion of pro-inflammatory cytokines like IL-4 and IL-13, which drive B-cell isotype switching to IgE. Therapeutic interventions, such as sublingual immunotherapy (e.g., Ragwitek), target this interaction by inducing peripheral T-cell tolerance or shifting the immune profile toward regulatory T-cells (Creticos et al., 2014). Monitoring the frequency and phenotype of T cells carrying these specific TCRs using pMHC tetramers serves as a valuable biomarker for assessing the efficacy of allergen-specific immunotherapy (FDA, 2014).

Other names

Amb a 1-specific T-cell receptorRagweed-specific T-cell receptorAmb a 1-pMHCII-specific TCRRagweed allergen-specific TCR

Induction of immunological tolerance through T-cell desensitization, anergy, or immune deviation from Th2 to Th1/Treg responses.