Definition

Allogeneic cytotoxic T lymphocytes (CTLs) that are specifically reactive to BK virus (BKV), with potential antiviral activity. Upon infusion of allogeneic BK-specific CTLs into immunocompromised patients who were infected with BKV after allogeneic stem cell transplantation, these cells exert a specific CTL response against BKV, thereby killing and eliminating the BKV-infected cells. BKV is a member of the polyomavirus family that may cause mild symptoms in normal, healthy people; however, BKV infection can lead to severe disease in immunocompromised patients.