Human Leukocyte Antigen – DR isotype (HLA-DR) – Tetanus toxin 830-844 (TT830-844) peptide complex (HLA-DR-TT830-844)

The Human Leukocyte Antigen – DR isotype (HLA-DR) – Tetanus toxin 830-844 (TT830-844) peptide complex is a molecular assembly where a specific 15-amino acid sequence (QYIKANSKFIGITEL) from the tetanus toxin protein is presented by the HLA-DR MHC Class II molecule (Panina-Bordignon et al., 1989, Eur. J. Immunol.). This epitope is widely characterized as "promiscuous" due to its ability to bind a broad range of HLA-DR alleles, making it a near-universal stimulator of CD4+ T-cells in the human population (Demotz et al., 1989, J. Immunol.). Biologically, the complex serves as a ligand for T-cell receptors (TCRs), initiating signaling cascades that lead to T-cell proliferation and cytokine production (UniProt: P01903). In clinical development, TT830-844 is frequently utilized as a "helper" epitope in peptide-based vaccines for cancer and infectious diseases to enhance the immunogenicity of less potent antigens (Slingluff, 2011, Cancer J.). Its role is pivotal in overcoming immune tolerance and ensuring a robust, multi-faceted immune response during immunotherapy.

Other names

TT830-844Tetanus toxin peptide 830-844Universal T-cell epitope TT830-844QYIKANSKFIGITELHLA-DR/TT830-844 complexTetanus toxin P2 epitope

The HLA-DR molecule presents the TT830-844 peptide to the T-cell receptor (TCR) of CD4+ helper T-cells. This interaction, in the presence of co-stimulatory signals, triggers T-cell activation, proliferation, and the secretion of cytokines such as IFN-gamma and IL-2, which provide "help" for B-cell antibody production and CD8+ T-cell responses (Demotz et al., 1989; Panina-Bordignon et al., 1989).