Epstein-Barr virus nuclear antigen 1 peptide–Human leukocyte antigen complex (EBNA1-HLA complex)

The Epstein-Barr virus nuclear antigen 1 (EBNA1) peptide–Human leukocyte antigen (HLA) complex is a primary immunological target for treating Epstein-Barr virus (EBV)-associated cancers. EBNA1 is a DNA-binding protein essential for the replication and mitotic segregation of the EBV genome, and it is the only viral protein consistently expressed in all EBV-related malignancies, such as Nasopharyngeal carcinoma and Burkitt lymphoma (Longnecker et al., 2013). The complex is formed when EBNA1 is processed into peptides and presented on the cell surface by HLA Class I or Class II molecules, signaling the presence of the virus to the immune system (Taylor et al., 2015). Because EBNA1 is absent in healthy human cells, these peptide-HLA complexes serve as highly specific tumor-associated antigens. Therapeutic approaches targeting this complex include adoptive T-cell therapies, such as Tabelecleucel, and engineered T-cell receptor (TCR) therapies designed to recognize specific EBNA1 epitopes (Prockop et al., 2020). These treatments aim to induce targeted lysis of malignant cells while sparing normal tissue, although challenges such as HLA downregulation and potential cross-reactivity with self-peptides remain significant considerations in drug development.

Other names

EBNA1-MHC complexEBV EBNA1-HLA complexEBNA1-HLA-DR complexEBNA1-HLA-A*02:01 complexEBV EBNA1-derived peptide-HLA complex

Recognition of the peptide-HLA complex by T-cell receptors (TCRs) or TCR-mimetic antibodies, triggering cytotoxic immune responses against EBV-positive malignant cells (Prockop et al., 2020).