BK polyomavirus major capsid protein VP1 peptide–Major Histocompatibility Complex (BKV VP1 pMHC)

BK polyomavirus (BKV) major capsid protein VP1 peptide–Major Histocompatibility Complex (MHC) is a molecular assembly consisting of a processed peptide fragment from the BKV VP1 protein presented on the surface of host cells within the MHC (Human Leukocyte Antigen or HLA) groove (Leboeuf et al., 2017). As the primary structural protein of the BKV capsid, VP1 contains several immunodominant epitopes that are critical for the activation of the adaptive immune system (UniProtKB - P03088). These pMHC complexes serve as the specific ligands for T-cell receptors (TCRs) on CD8+ and CD4+ T cells, facilitating the identification and destruction of BKV-infected cells (Papadopoulou et al., 2017). In immunocompromised individuals, such as kidney transplant recipients, the failure of the immune system to recognize these complexes can lead to BKV reactivation, resulting in BK virus-associated nephropathy (BKVAN) or hemorrhagic cystitis (Bohl et al., 2019). Therapeutic interventions often focus on these complexes through adoptive T-cell transfer or the development of peptide-based vaccines to restore or enhance BKV-specific immunity (Papadopoulou et al., 2017). Additionally, synthetic pMHC multimers are utilized as diagnostic tools to quantify and characterize the T-cell response in clinical monitoring.

Other names

BKV VP1 peptide-HLA complexBK virus VP1 pMHCBKV VP1-MHC complexBK polyomavirus VP1 antigen-MHC complex

Recognition by T-cell receptors (TCRs) on cytotoxic T lymphocytes, triggering the release of perforin and granzymes to induce apoptosis in virally infected cells.