T-cell receptor on CD4+ T-cell specific for grass pollen-derived peptide (TCR)

T-cell receptors (TCRs) on CD4+ T-cells specific for grass pollen-derived peptides are the primary molecular sensors that initiate and drive the allergic immune response to grass pollen. These receptors recognize specific allergenic epitopes, such as those from the Phl p 1 and Phl p 5 proteins of Timothy grass, presented by Major Histocompatibility Complex (MHC) class II molecules on the surface of antigen-presenting cells (Wambre et al., 2012, Science Translational Medicine). In allergic individuals, the activation of these TCRs leads to the differentiation of Type 2 helper T-cells (Th2), which secrete pro-inflammatory cytokines like IL-4 and IL-13, ultimately resulting in IgE production and the clinical symptoms of hay fever and asthma (Larché et al., 2006, Nature Reviews Immunology). Therapeutic strategies, particularly allergen-specific immunotherapy (AIT), aim to modify the signaling through these TCRs to induce immunological tolerance. This process involves the induction of regulatory T-cells (Tregs) and the shifting of the immune response from a Th2 to a Th1 or regulatory profile (Akdis & Akdis, 2014, Journal of Allergy and Clinical Immunology). Monitoring the frequency and phenotype of these specific TCR-bearing cells using MHC tetramers is a vital tool for evaluating the success of desensitization treatments.

Other names

Grass pollen-specific T-cell receptorAllergen-specific TCRTimothy grass-specific TCRPhl p-specific TCR

Induction of immune tolerance through T-cell anergy, clonal deletion, or the promotion of regulatory T-cells (Tregs) and immune deviation from a Th2 to a Th1 profile.