Hepatitis C virus nonstructural protein 3 epitope 1406–1415 (HCV NS3 1406 epitope)

The Hepatitis C virus nonstructural protein 3 epitope 1406–1415 (commonly known as the HCV NS3 1406 epitope) is an immunodominant, HLA-A*02-restricted peptide within the NS3 protein of HCV. Its most recognized prototype sequence is KLSGLGLNAV, although multiple naturally occurring variants (e.g., KLSSLGLNAV, KLSGLGINAV, KLSALGLNAV) exist due to the high mutation rate of HCV[1][2][7]. This epitope is a principal target for CD8+ cytotoxic T lymphocytes, contributing to viral clearance during acute infection and associated with immune exhaustion in chronic infection. Sequence variability in this epitope facilitates viral immune escape, influencing disease persistence and presenting a significant barrier to effective T cell-based vaccines[1][2][7]. Chronic HCV infection is characterized by increased PD-1/Tim-3 expression on CD8+ T cells responding to this epitope, indicative of T cell exhaustion[1]. This region is a focus of immunotherapeutic and vaccine research, although no approved drugs currently target it directly[1][2][3][7].

Other names

NS3 1406HCV NS3 1406–1415 epitopeHCV 1406 epitopeNS3 1406–1415HCV NS3 KLSGLGLNAV (prototype sequence)HLA-A*02-restricted NS3 1406 epitope

Target of vaccine candidate CD8+ T cell responses (experimental: T cell-based immunotherapy and vaccine research); Site of immune escape via viral mutation; Elicits HLA-A*02:01-restricted cytotoxic T lymphocyte (CTL) responses