BK polyomavirus peptide–Human Leukocyte Antigen complex (BKV peptide–HLA complex)

The BK polyomavirus (BKV) peptide–Human Leukocyte Antigen (HLA) complex is a molecular assembly presented on the surface of host cells, primarily renal tubular epithelial cells, during BKV infection or reactivation (Hirsch et al., 2019, PMID: 31205004). This complex is formed when viral proteins, such as the Large T-antigen or VP1 capsid protein, are proteolytically processed into short peptides and loaded onto HLA Class I or Class II molecules (O'Reilly et al., 2016, PMID: 27606771). These complexes serve as the primary signal for the adaptive immune system, specifically allowing BKV-specific T-cell receptors (TCRs) to identify and destroy infected cells. In healthy individuals, robust T-cell responses keep the virus in a latent state, but in immunocompromised patients, such as kidney transplant recipients, the virus can reactivate (Sawinski & Goral, 2015, PMID: 25831514). Reactivation leads to BKV-associated nephropathy (BKVAN), a serious condition that can result in graft loss and chronic kidney disease. Therapeutic interventions targeting these complexes include adoptive T-cell therapies, such as posoleucel (ALVR105), which utilize donor-derived T cells to recognize specific BKV peptide-HLA combinations (Allovir, 2023). By restoring immune surveillance through the recognition of these complexes, these therapies aim to reduce viral load and prevent tissue damage. Monitoring BKV DNA levels and HLA compatibility is essential for the clinical management and efficacy of these targeted treatments.

Other names

BK virus peptide–MHC complexBKV-HLA complexBKV-specific pMHCBK polyomavirus antigen-HLA complex

T-cell receptor (TCR) mediated recognition of the peptide-HLA complex leading to cytotoxic T lymphocyte (CTL) activation and lysis of infected host cells (O'Reilly et al., 2016, PMID: 27606771).