Epstein-Barr virus lytic antigen peptide-HLA complex (EBV lytic pHLA)

Epstein-Barr virus (EBV) lytic antigen peptide-HLA complexes are molecular assemblies consisting of viral peptides derived from the lytic phase of the EBV life cycle bound to Human Leukocyte Antigen (HLA) class I or II molecules. These complexes are displayed on the surface of infected cells, particularly during active viral replication or in certain EBV-associated malignancies where lytic gene expression occurs, such as nasopharyngeal carcinoma and post-transplant lymphoproliferative disorder (PTLD) [PMID: 31534003, PMID: 33806170]. The lytic cycle is initiated by immediate-early proteins such as BZLF1 (Zta) and BRLF1 (Rta), which are highly immunogenic and serve as primary targets for cytotoxic T lymphocytes (CTLs) [PMID: 15141007]. In therapeutic applications, these complexes are targeted by adoptive T-cell therapies, such as Tabelecleucel, and experimental TCR-T cell products designed to recognize specific peptide-HLA combinations like BZLF1-derived peptides presented by HLA-A*02:01 [PMID: 36516557]. Targeting lytic antigens is particularly effective because these proteins are expressed early in the viral reactivation process, allowing the immune system to eliminate infected cells before progeny virions are released. However, therapeutic success can be limited by viral mechanisms that downregulate HLA expression or by the requirement for precise HLA matching in allogeneic cell therapies [PMID: 28923915].

Other names

EBV lytic pMHCEBV lytic peptide-MHC complexEBV lytic antigen-HLA complexEpstein-Barr virus lytic peptide-HLA complex

Recognition of the specific viral peptide-HLA complex by the T-cell receptor (TCR) of an effector T cell, leading to the formation of an immunological synapse, release of perforin and granzymes, and subsequent apoptosis of the target cell [PMID: 31534003].