Human telomerase reverse transcriptase (hTERT) 540-548 epitope (hTERT 540-548)

The human telomerase reverse transcriptase (hTERT) 540-548 epitope is a nonameric peptide sequence (ILAKFLHWL) derived from the catalytic subunit of the telomerase enzyme (UniProt P10613). Telomerase is a ribonucleoprotein complex responsible for maintaining telomere length, a function that is essential for the replicative immortality of approximately 85-90% of human cancers (PubMed 24651525). In contrast, telomerase activity is absent or very low in most normal adult somatic cells, making hTERT a highly attractive tumor-associated antigen for targeted immunotherapy (NCI Thesaurus). The 540-548 epitope is specifically presented on the cell surface by the HLA-A*0201 major histocompatibility complex (MHC) class I molecule (PubMed 12193314). Therapeutic agents like the VX-001 vaccine utilize this epitope to stimulate the production of cytotoxic T-lymphocytes (CTLs) that can selectively recognize and destroy hTERT-expressing malignant cells (Vaxon Biotech). Because of its broad expression across different tumor types, this epitope is being investigated as a target for universal cancer vaccines. Clinical development has primarily focused on its application in solid tumors such as non-small cell lung cancer and prostate carcinoma (ClinicalTrials.gov NCT00341159). Monitoring for HLA-A*0201 status is a critical biomarker for patient selection in therapies targeting this specific epitope.

Other names

ILAKFLHWLhTERT 540TERT 540-548Telomerase reverse transcriptase peptide 540-548

Induction of HLA-A*0201-restricted cytotoxic T-lymphocyte (CTL) response against hTERT-expressing cells.