Unravelling the role of BK polyomavirus genetic variants in viral pathogenicity and clearance in kidney transplant recipients

BK polyomavirus is the first human polyomavirus discovered in the early 70s in a kidney transplant patient. The immunosuppression state of the patient can lead to reactivation of the virus, leading in 30% of the case to graft loss. Up to now, no protocol for the management of BKPyV associated nephropathy has been established. The combination of immunosuppressive drug tapering and cidofovir (an anti-DNA virus agent) permits in many cases to control the viral replication and the integrity of the graft. However, in some patients, this therapeutic strategy does not result in the control of the viral infection and graft loss ensues.

In this project, the genomic variation of BKPyV isolated from kidney-transplant patients that respond successfully to the combination therapy (immunosuppressive reduction + antiviral treatment) and from patients in therapeutic failure will be analyzed. This genomic analysis will allow to identify natural variants within the BKPyV that confer resistance to cidofovir treatment and identify patients with BKPyV associated nephropathy that are likely to benefit from cidofovir-based therapy.