[18F]fluoro-arabinofuranosyl guanine

[18F]fluoro-arabinofuranosyl guanine ([18F]F-AraG), marketed under the trade name VisAcT, is a small molecule PET radiotracer developed by CellSight Technologies. It is a fluorine-18 labeled analog of nelarabine, designed to image activated T-cells. The tracer selectively accumulates in activated immune cells, particularly CD8+ T-cells, because it serves as a substrate for deoxycytidine kinase (dCK) and deoxyguanosine kinase (dGK), enzymes that are highly active during T-cell proliferation and activation. This mechanism allows for the non-invasive monitoring of immune responses in oncology (e.g., profiling immunotherapy response), graft-versus-host disease (GVHD), and neuroinflammatory conditions such as Alzheimer's disease.

Brand names

VisAcT

Other names

2'-deoxy-2'-[18F]fluoro-9-β-D-arabinofuranosylguanine[18F]F-Ara-G