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

The BK polyomavirus (BKV) VP1 capsid protein-derived peptide-HLA class I complex is a critical immunological target for the management of BKV-related complications in immunocompromised patients, particularly kidney and hematopoietic stem cell transplant recipients (PubMed: 25143484). VP1 is the major structural protein of the BKV capsid, and its degradation products are processed and presented on the cell surface by Human Leukocyte Antigen (HLA) class I molecules (UniProt: P03088). These peptide-HLA complexes are specifically recognized by the T-cell receptors (TCRs) of CD8+ cytotoxic T lymphocytes, which play a primary role in controlling viral replication (PubMed: 19158269). In the absence of effective T-cell immunity, BKV can cause BK polyomavirus-associated nephropathy (BKVAN) or hemorrhagic cystitis. Therapeutic strategies targeting this complex include the adoptive transfer of donor-derived or "off-the-shelf" BKV-specific T cells, such as Posoleucel, which aim to restore the host's ability to clear infected cells (PubMed: 31534015). Monitoring the presence of these complexes and the corresponding T-cell response is essential for assessing the risk of viral reactivation and the efficacy of immunotherapy. This target is particularly relevant for patients who do not respond to standard reduction of immunosuppression.

Other names

BKV VP1 peptide-MHC complexBK virus VP1 antigenBKV VP1-HLA class I complexBKV VP1-derived epitopesBKV VP1-HLA-A*02:01 complex

Recognition of the peptide-HLA complex by the T-cell receptor (TCR) of CD8+ cytotoxic T lymphocytes, triggering the release of perforins and granzymes to induce apoptosis in BKV-infected cells (PubMed: 25143484).