HLA-A2-restricted Prostate-Specific Membrane Antigen and TCR Gamma Alternate Reading Frame Protein peptide-MHC complexes (HLA-A2-PSMA/TARP)

The HLA-A2-restricted presentation of PSMA (Prostate-Specific Membrane Antigen) and TARP (TCR Gamma Alternate Reading Frame Protein) epitopes is a specialized immunological target configuration used primarily in the development of immunotherapies for prostate cancer. PSMA is a well-characterized type II transmembrane glycoprotein that is significantly upregulated in prostate cancer cells and the neovasculature of various solid tumors (UniProt Q04609). TARP is a protein expressed predominantly in the prostate and in certain breast cancer subtypes, making it a highly specific target for T-cell mediated attacks (PubMed: 24563474). In individuals carrying the HLA-A*02:01 allele, specific peptide sequences from these proteins are processed and displayed on the cell surface, where they can be recognized by the T-cell receptors (TCRs) of CD8+ cytotoxic T lymphocytes. Therapeutic interventions targeting these complexes include peptide-based vaccines and adoptive cell therapies, such as TCR-engineered T cells. For instance, the National Cancer Institute (NCI) has investigated TARP multi-peptide vaccines in patients with biochemical recurrence of prostate cancer, demonstrating the ability to slow PSA doubling times by inducing targeted immune responses (PubMed: 24563474). Similarly, PSMA-derived epitopes restricted by HLA-A2 have been used to develop TCR-T therapies designed to recognize and eliminate malignant cells (PubMed: 11156400). The primary challenge in targeting these complexes lies in ensuring high specificity to avoid off-target effects on normal tissues, such as the salivary glands, where PSMA is also expressed, and managing potential immune escape mechanisms like HLA class I downregulation.

Other names

PSMA/TARP HLA-A2 epitopesHLA-A*02:01 restricted PSMA and TARP peptidesProstate-specific membrane antigen and TCR gamma alternate reading frame protein MHC-I complexes

Induction of antigen-specific CD8+ cytotoxic T-lymphocyte responses by presenting specific PSMA and TARP peptide fragments via the HLA-A*02:01 molecule to T-cell receptors.