Human polyomavirus 1 (BK polyomavirus) (BKV)

Human polyomavirus 1, commonly known as BK polyomavirus (BKV), is a double-stranded DNA virus that establishes lifelong latency in the renal tubular cells and urothelium of a majority of the global population (PubMed: 29437630). In immunocompromised individuals, particularly kidney transplant recipients and hematopoietic stem cell transplant patients, BKV can reactivate and cause severe conditions such as BK virus-associated nephropathy (BKVAN) and hemorrhagic cystitis (PubMed: 30811461). The virus hijacks the host's cellular machinery to replicate, often utilizing the Large T-antigen to drive the cell into the S-phase of the cell cycle (UniProt: P03072). Therapeutic strategies include the off-label use of antivirals like cidofovir, which inhibits viral DNA synthesis, and emerging adoptive immunotherapies like virus-specific T-cells (VSTs) that target infected cells expressing viral antigens (PubMed: 34162817). Managing BKV infection often involves a delicate balance between reducing immunosuppressive drugs to allow for natural immune clearance and avoiding the risk of organ transplant rejection.

Other names

BK virusBKPyVPolyomavirus hominis 1BK virus infected cells

Drugs targeting BK virus-infected cells primarily act by inhibiting viral DNA polymerase to stop replication (e.g., Cidofovir), or by utilizing virus-specific T-cells (VSTs) to recognize viral antigens like the Large T-antigen and VP1 protein on the surface of infected cells, leading to targeted cell lysis (e.g., Posoleucel).