Cytomegalovirus phosphoprotein 65 peptide (495-503) presented by Human Leukocyte Antigen A*02:01 (pp65(495-503)/HLA-A*02:01 complex)

The Cytomegalovirus phosphoprotein 65 (pp65) peptide (495-503) presented by Human Leukocyte Antigen A*02:01 (HLA-A*02:01) is a specific peptide-major histocompatibility complex (pMHC) class I assembly found on the surface of cells infected with Human Cytomegalovirus (CMV). This complex consists of the immunodominant nonamer peptide NLVPMVATV, derived from the CMV pp65 protein (UL83), bound within the peptide-binding groove of the HLA-A*02:01 molecule (PubMed: 10438932). As a primary target for the host CD8+ T-cell response, this complex plays a vital role in the immune surveillance and control of CMV, which can cause severe disease in immunocompromised individuals such as transplant recipients (PubMed: 31534003). Therapeutic strategies targeting this complex include adoptively transferred virus-specific T cells (VSTs) and T-cell receptor (TCR) engineered T cells designed to recognize the NLVPMVATV/HLA-A*02:01 epitope with high specificity (PubMed: 28928240). By engaging this target, these therapies facilitate the selective destruction of CMV-infected cells, thereby reducing viral load and preventing clinical manifestations like CMV retinitis or pneumonitis. Additionally, the complex is a critical tool in diagnostic assays, such as MHC tetramer staining, used to monitor CMV-specific immune reconstitution in patients (PubMed: 11748170).

Other names

NLVPMVATV/HLA-A*02:01 complexCMV pp65(495-503) pMHCHLA-A*02:01/NLVPMVATVpCMV-pp65(495-503)/HLA-A*02:01HLA-A2/pp65(495-503)

T-cell receptor (TCR) mediated recognition of the peptide-MHC complex on the surface of infected cells, triggering cytotoxic T-lymphocyte (CTL) activation and subsequent lysis of the target cell via the release of perforins and granzymes.