BK polyomavirus peptide-Major Histocompatibility Complex (BKV pMHC)

BK polyomavirus (BKV) peptide-Major Histocompatibility Complex (pMHC) complexes are molecular assemblies consisting of viral protein fragments (peptides) bound to host MHC (HLA) molecules on the surface of infected cells (Source: Frontiers in Immunology, 2021). These complexes are essential for the immune system's recognition of BKV, a double-stranded DNA virus that typically remains latent but can cause severe complications like BKV-associated nephropathy (BKVAN) and hemorrhagic cystitis in immunocompromised individuals, particularly kidney and bone marrow transplant recipients (Source: Journal of Clinical Investigation, 2017). The peptides are derived from BKV proteins such as the Large T-antigen and the major capsid protein VP1 (Source: Journal of Virology, 2019). These pMHC complexes serve as the primary target for CD8+ cytotoxic T-lymphocytes, which recognize them via specific T-cell receptors (TCRs). In therapeutic contexts, these complexes are targeted by adoptive T-cell therapies, including virus-specific T-cells (VSTs) like Posoleucel and TCR-engineered T-cells, to restore viral control and clear infection (Source: AlloVir, 2023). Monitoring these complexes and the corresponding T-cell response is crucial for managing post-transplant viral reactivation and ensuring patient safety (Source: American Journal of Transplantation, 2020).

Other names

BKV peptide-HLA complexBK virus pMHCBKV-specific epitope-MHC

Targeted recognition by T-cell receptors (TCRs) on cytotoxic T-lymphocytes, which triggers the release of cytotoxic granules (perforin/granzyme) to induce apoptosis in BKV-infected cells.