PyVST

PyVST refers to polyomavirus-specific T cells, an investigational cell therapy developed for the treatment of progressive multifocal leukoencephalopathy (PML), a rare and often fatal demyelinating disease of the central nervous system caused by JC polyomavirus (JCV) in immunosuppressed individuals. PyVST are ex vivo expanded virus-specific T lymphocytes generated from peripheral blood mononuclear cells of partially HLA-matched healthy donors—typically first-degree relatives. These donor-derived T cells are stimulated with peptide libraries derived from BK polyomavirus proteins (Large T antigen and VP1), which share high sequence homology with JCV antigens, enabling cross-recognition and targeting of JCV-infected cells. The therapy aims to restore adaptive immunity against JCV by infusing these allogeneic, partially HLA-matched cytotoxic T lymphocytes into patients with PML[1][3][7]. Clinical studies have demonstrated feasibility and safety in early-phase trials[3][7].

Other names

polyomavirus-specific T cellspolyoma virus specific T cellsBKV-specific T cells