Tyrosinase (TYR) antigenic epitope presented on MHC class II (TYR/MHC-II)

Tyrosinase (TYR) is a copper-containing enzyme essential for melanin biosynthesis, primarily expressed in melanocytes and highly overexpressed in melanoma (UniProt: P14679). The TYR antigenic epitope presented on MHC class II refers to specific peptide fragments derived from the tyrosinase protein that are displayed by Major Histocompatibility Complex class II molecules, such as HLA-DR, to CD4+ T helper cells (PubMed: 8144908). This presentation is a critical component of the adaptive immune response against melanoma, as CD4+ T cells provide essential cytokines and signals for the activation of cytotoxic CD8+ T cells and B cells (PubMed: 9743334). In therapeutic contexts, these epitopes are targeted using peptide-based vaccines or T-cell receptor (TCR) engineered therapies to stimulate a targeted immune attack against tumor cells. Clinical trials have explored various tyrosinase-derived peptides, such as those restricted by HLA-DRB1*04:01, to treat patients with advanced melanoma (ClinicalTrials.gov: NCT00001578). While effective in inducing immune responses, targeting tyrosinase can lead to the destruction of healthy melanocytes, resulting in autoimmune vitiligo as a common side effect. The specificity of these epitopes makes them valuable for personalized immunotherapy, particularly in patients with specific HLA genotypes.

Other names

Tyrosinase peptide-MHC class II complexHLA-DR-restricted tyrosinase epitopeTYR-derived MHC II epitopeTyrosinase epitope

Stimulation of CD4+ T-helper cells to recognize and eliminate cells expressing tyrosinase-derived peptides in the context of MHC class II molecules.