Grass allergen-specific T cell receptor (Grass-TCR)

Grass allergen-specific T cell receptors (TCRs) are specialized heterodimeric proteins expressed on the surface of CD4+ T lymphocytes that mediate the recognition of grass pollen antigens. These receptors specifically bind to allergenic peptides, such as those derived from Phleum pratense (Timothy grass), when they are presented by Major Histocompatibility Complex (MHC) class II molecules on antigen-presenting cells (Wambre et al., 2012, Sci Transl Med). In sensitized individuals, this interaction triggers a Th2-biased immune response, leading to the production of cytokines like IL-4 and IL-13, which drive IgE synthesis and allergic inflammation (Larché et al., 2006, Nat Rev Immunol). This pathological activation is the primary driver of symptoms in allergic rhinitis and allergic asthma. As a therapeutic target, these TCRs are modulated through allergen-specific immunotherapy (AIT), which aims to reprogram the immune system toward tolerance. AIT works by inducing T-cell anergy, deleting effector Th2 cells, and promoting the expansion of regulatory T cells (Tregs) that suppress allergic inflammation (Akdis & Akdis, 2014, Nat Rev Drug Discov). Monitoring these TCRs using MHC-peptide tetramers serves as a critical biomarker for assessing the frequency of allergen-specific T cells and the efficacy of desensitization treatments (Wambre et al., 2014, J Allergy Clin Immunol). While highly effective, targeting these receptors with whole allergens carries a risk of systemic IgE-mediated reactions, necessitating careful clinical supervision.

Other names

Grass pollen-specific TCRTimothy grass allergen-specific T-cell receptorPhl p-specific TCRMHC class II-restricted grass allergen TCRAllergen-specific T cell receptors on CD4+ T cells recognizing grass-allergen–derived peptides presented by MHC class II

Induction of immune tolerance through T-cell anergy, deletion of pathogenic Th2 cells, or immune deviation from Th2 to Th1/Treg responses (Akdis & Akdis, 2014, Nat Rev Drug Discov).