BK polyomavirus VP3 capsid protein-derived peptide-HLA class I complex (BKV VP3-HLA-I)

The BK polyomavirus (BKV) VP3 capsid protein-derived peptide-HLA class I complex is a specific molecular assembly consisting of a fragment from the BKV minor capsid protein VP3 bound to a host Human Leukocyte Antigen (HLA) class I molecule [1, 2]. This complex is expressed on the surface of cells infected with BKV, a virus that frequently reactivates in immunocompromised individuals, such as those undergoing organ or stem cell transplantation [3, 4]. The primary biological role of this complex is to serve as an epitope for recognition by CD8+ cytotoxic T lymphocytes (CTLs) via their T-cell receptors (TCRs) [2, 5]. In clinical settings, BKV reactivation can lead to devastating complications including BKV-associated nephropathy (BKVAN) and hemorrhagic cystitis [3, 4]. Therapeutic strategies targeting this complex involve the use of virus-specific T cells (VSTs) or TCR-engineered T cells that specifically bind to the VP3-HLA complex to induce the death of infected cells [6, 7]. These therapies aim to restore the patient's cellular immunity against the virus without causing significant damage to the transplanted organ or inducing systemic toxicity [7, 8]. Monitoring the viral load and the presence of VP3-specific T cells are essential for managing patient outcomes and evaluating the success of these targeted immunotherapies [8]. Sources: [1] UniProt (P03094); [2] Pelloquin et al. (2018) Front Immunol; [3] Hirsch & Randhawa (2019) Am J Transplant; [4] NIH StatPearls (BK Virus); [5] Blyth et al. (2011) Blood; [6] AlloVir (Posoleucel); [7] Tzannou et al. (2017) J Clin Oncol; [8] Leboeuf et al. (2017) Am J Transplant.

Other names

BKV VP3 antigen-HLA complexBK virus VP3 peptide-MHC class IBKV VP3-MHC complexBKV VP3-HLA complex

Recognition of the peptide-HLA complex by specific T-cell receptors (TCRs) on CD8+ T cells, triggering cytotoxic activity and lysis of infected cells.