Epstein-Barr virus BZLF1 peptide-HLA class I complex (EBV BZLF1-HLA-I) (EBV BZLF1-HLA-I)

The Epstein-Barr virus (EBV) BZLF1 peptide-HLA class I complex is a molecular assembly consisting of a peptide fragment derived from the EBV lytic protein BZLF1 bound to a Human Leukocyte Antigen (HLA) class I molecule. BZLF1, also known as Zta or ZEBRA, is an immediate-early transcription factor that acts as the master switch for EBV reactivation from its latent state to the lytic cycle (PMID: 10823895). These complexes are displayed on the surface of infected cells, where they serve as the primary signal for recognition by CD8+ cytotoxic T lymphocytes (CTLs) (PMID: 9126268). Because BZLF1 is one of the first proteins expressed during viral reactivation, it is a highly effective target for the immune system to intercept the production of new viral particles. In therapeutic development, these complexes are targeted by adoptive T-cell therapies, such as tabelecleucel, and engineered TCR-T cells to treat EBV-associated malignancies like post-transplant lymphoproliferative disorder (PTLD) and nasopharyngeal carcinoma (PMID: 31533978). The most well-characterized epitope within this complex is the RAKFKQLL peptide presented by HLA-B*08:01, which is immunodominant in many EBV-seropositive individuals. Therapeutic strategies often involve the use of TCR-like antibodies or T-cell receptors engineered to bind these specific complexes with high affinity. Challenges in targeting this complex include the virus's ability to downregulate HLA expression to evade detection and the potential for T-cell exhaustion in chronic infection settings (PMID: 25609774).

Other names

BZLF1-MHC class I complexZEBRA peptide-HLA complexZta peptide-HLA complexEB1 peptide-HLA complexRAKFKQLL-HLA-B*08:01 complexBZLF1-HLA-I complex

Targeting of EBV-infected cells via T-cell receptor (TCR) recognition of the peptide-HLA complex, leading to granzyme/perforin-mediated apoptosis.