Epstein-Barr virus nuclear antigen 3 peptide–Major Histocompatibility Complex class I complex (EBV EBNA3-pMHC)

The Epstein-Barr virus nuclear antigen 3 (EBNA3) peptide–Major Histocompatibility Complex (MHC) class I complex is a cell-surface molecular assembly essential for the immune surveillance of EBV-infected cells. It consists of an 8- to 11-amino acid peptide derived from the EBNA3A, EBNA3B, or EBNA3C viral proteins non-covalently bound within the groove of an MHC class I molecule (HLA). These complexes are primarily presented on the surface of B-lymphocytes during the latent phase of the viral life cycle, where EBNA3 proteins play a critical role in cell cycle regulation and host cell transformation (PMID: 23536651). The complex is specifically recognized by the T-cell receptors (TCRs) of CD8+ cytotoxic T lymphocytes, which is the primary mechanism for controlling EBV infection in healthy individuals. In patients with impaired immunity, such as those undergoing organ transplantation, the failure of this recognition leads to EBV-driven malignancies like post-transplant lymphoproliferative disorder (PTLD). Consequently, these pMHC complexes are major targets for adoptive cellular therapies, including EBV-specific T-cells (e.g., tabelecleucel) and engineered TCR-T cell therapies designed to restore or augment the anti-viral immune response (PMID: 36516543).

Other names

EBNA3-HLA complexEBV EBNA3-MHC I complexEBNA3 peptide-MHC class I complexEBNA3A/B/C-pMHC

Recognition by antigen-specific T-cell receptors (TCRs) on CD8+ T cells, leading to the release of perforin and granzymes and subsequent apoptosis of the EBV-infected cell.