Epstein–Barr virus BZLF1 peptide–major histocompatibility complex (EBV BZLF1-pMHC)

The Epstein–Barr virus (EBV) BZLF1 peptide–major histocompatibility complex (pMHC) is a critical immunological target found on the surface of cells undergoing the EBV lytic cycle. BZLF1, also known as Zta or EB1, is an immediate-early protein that serves as the master switch for transitioning the virus from a latent state to active lytic replication. During this process, BZLF1-derived peptides, most notably the RAKFKQLL epitope, are processed and presented on the cell surface by MHC Class I molecules, particularly HLA-B*08:01. This presentation allows the immune system, specifically CD8+ cytotoxic T cells, to recognize and eliminate cells harboring replicating virus. In the context of therapeutic development, the BZLF1-pMHC complex is a primary target for adoptive T-cell therapies and TCR-engineered T cells (TCR-T). Because BZLF1 is expressed early in the lytic cycle and is essential for viral production, targeting this complex can effectively control EBV-associated diseases such as post-transplant lymphoproliferative disorder (PTLD) and certain EBV-positive malignancies. Drugs like Tabelecleucel utilize EBV-specific T cells that recognize these complexes to treat patients with EBV-driven lymphoproliferative diseases. Research continues into high-affinity TCRs and TCR-like antibodies that can bind this complex with high specificity to minimize off-target effects while maximizing anti-viral efficacy.

Other names

EBV Zta peptide-HLA complexEBV EB1 peptide-MHC complexBZLF1-HLA-B*08:01 complexRAKFKQLL-HLA-B*08:01 complexEpstein-Barr virus lytic antigen-MHC complex

Targeting of the peptide-MHC complex by T-cell receptors (TCRs) or TCR-like molecules to induce selective lysis of EBV-infected cells undergoing lytic reactivation.