Myeloperoxidase-derived peptide PR1 bound to HLA class I histocompatibility antigen A*02 alpha chain (PR1-HLA-A*02 (commonly referred to as PR1 peptide presented by HLA-A2))

The "Myeloperoxidase-derived peptide PR1 bound to HLA class I histocompatibility antigen A*02 alpha chain" refers to a peptide epitope (PR1), typically 9 amino acids in length, derived from the cleavage products of myeloperoxidase or proteinase 3 (two enzymes found in myeloid lineage cells). When this peptide is bound within the groove of the HLA-A*02:01 molecule, it forms a complex that is displayed on the cell surface for recognition by CD8+ cytotoxic T lymphocytes. Cells presenting the PR1/HLA-A*02 complex—including many leukemia blast cells—can be targeted for immune-mediated destruction. This specific peptide-MHC combination is being investigated as a target for T cell-based immunotherapies due to its restricted expression in malignant cells and its immunogenic potential[1][5][7][9]. The HLA-A*02 molecule is a common MHC Class I molecule, presenting intracellular peptides to the immune system, and the PR1 epitope is a well-characterized leukemia-associated antigen used in ongoing immunotherapy research[2][4][6][8].

Other names

PR1 peptide-HLA-A2 complexPR1/HLA-A*0201 complexPR1 peptide presented by HLA-A*02PR1 epitope/HLA-A*02

Immune activation: PR1 peptide presented by HLA-A*02 on the cell surface is recognized by cytotoxic CD8+ T cells, leading to targeted killing of tumor/leukemia cells. Tumor antigen targeting: PR1-specific T cells or vaccines trigger immune-mediated lysis of cells displaying the PR1 peptide-HLA-A*02 complex.