BK virus peptide–Major Histocompatibility Complex (BKV pMHC)

BK virus peptide–Major Histocompatibility Complex (pMHC) complexes are molecular structures formed by the association of BK polyomavirus-derived peptides with host MHC (Human Leukocyte Antigen or HLA) molecules on the surface of infected cells. These complexes serve as the essential signal for the adaptive immune system, specifically CD8+ cytotoxic T lymphocytes, to identify and eliminate virally infected cells. In healthy individuals, the immune system effectively monitors these pMHC complexes to keep the virus in a latent state; however, in immunocompromised patients, such as kidney transplant recipients, the failure of this recognition leads to viral reactivation. This reactivation can result in severe clinical outcomes, including BK virus-associated nephropathy (BKVAN) and hemorrhagic cystitis. Therapeutic interventions targeting these complexes primarily involve adoptive T-cell therapies, where virus-specific T cells (VSTs) are infused into patients to recognize BKV pMHC and restore viral control. Additionally, pMHC multimers are used as diagnostic tools to quantify the endogenous T-cell response against the virus in clinical settings.

Other names

BK polyomavirus peptide-HLA complexBKV pMHC complexBK virus antigen-MHC complexBKV-specific peptide-MHC

Adoptive cellular immunotherapy involving the recognition of viral peptides presented by MHC molecules by cytotoxic T-cell receptors, leading to the targeted lysis of BK virus-infected cells.