CD4+ T cells specific for Ambrosia elatior allergen-derived peptides (Ragweed-specific CD4+ T cells)

CD4+ T cells specific for Ambrosia elatior (common ragweed) allergen-derived peptides are a specialized population of helper T lymphocytes that orchestrate the allergic immune response to ragweed pollen. These cells recognize specific peptide epitopes, primarily derived from the major allergen Amb a 1, when presented by MHC class II molecules on the surface of antigen-presenting cells [Ndhlovu et al., 2012]. In sensitized individuals, these T cells predominantly adopt a Th2 phenotype, secreting pro-inflammatory cytokines such as IL-4, IL-5, and IL-13 that drive the production of allergen-specific IgE and the recruitment of eosinophils, leading to the clinical symptoms of allergic rhinitis and asthma [Wopfner et al., 2005]. As a therapeutic target, these cells are modulated through allergen-specific immunotherapy (AIT) to restore immune tolerance. AIT works by inducing a state of peripheral T-cell tolerance through mechanisms such as T-cell anergy, deletion, or the induction of regulatory T cells (Tregs) that suppress allergic inflammation via the secretion of IL-10 and TGF-beta [Akdis & Akdis, 2014]. Current therapeutic agents targeting these cells include standardized ragweed pollen extracts for sublingual or subcutaneous administration, as well as investigational peptide-based vaccines designed to provide the necessary T-cell stimulus while minimizing the risk of IgE-mediated systemic reactions [Larché, 2007].

Other names

Amb a 1-specific CD4+ T cellsRagweed-reactive T helper cellsCommon ragweed-specific T cellsAmbrosia elatior-reactive T lymphocytes

Induction of peripheral T-cell tolerance through mechanisms such as T-cell anergy, immune deviation from Th2 to Th1 phenotypes, and the expansion of IL-10-secreting regulatory T cells (Tregs) [Akdis & Akdis, 2014].