BK polyomavirus VP1 capsid protein-derived peptide-HLA complex (BKV VP1-HLA complex)

BK polyomavirus (BKV) is a double-stranded DNA virus that remains latent in the urinary tract of most healthy individuals but can reactivate in immunocompromised patients, particularly kidney and hematopoietic stem cell transplant recipients (PMID: 30135633). The VP1 capsid protein is the major structural component of the virus and a primary target for the host's cellular immune response (PMID: 18434598). Viral peptide–HLA complexes derived from VP1 are presented on the surface of infected cells, where they are recognized by the T-cell receptors (TCRs) of CD8+ and CD4+ T lymphocytes (PMID: 25605962). This recognition is crucial for the clearance of the virus and the prevention of diseases such as BKV-associated nephropathy (BKVAN) and hemorrhagic cystitis. In the context of drug development, these complexes serve as the specific targets for adoptive T-cell therapies, such as Posoleucel (ALVR105), where donor-derived or engineered T-cells are infused into patients to restore viral immunity (NCT04390113). Monitoring the presence and frequency of T-cells specific to these VP1-HLA complexes is a key biomarker for assessing a patient's risk of BKV-related complications and the efficacy of immunotherapy (PMID: 21937619).

Other names

BKV VP1-MHC complexBK virus VP1 antigen-HLA complexVP1-specific peptide-MHCBKV VP1-specific T-cell target

T-cell receptor binding and subsequent cytotoxic T-lymphocyte mediated lysis of infected cells