Imaging Immune Activation in HIV by PET-MR

The PET radiofluorinated imaging agent, \[18F\]F-AraG (2'-deoxy-2'-fluoro-9-β-D-arabinofuranosylguanine; trade name VisAcT) localizes to sites of immune activation and is predominantly accumulated in proliferative T cells. As a result, there is interest in imaging residual immune activation in the setting of both treated and untreated HIV-1 infection, a disease in which chronic immune activation and inflammation may lead to significant morbidity, despite the use of otherwise suppressive ART. The primary endpoint is to determine the anatomical distribution of \[18F\]F-AraG in HIV-infected individuals taking or not taking antiretroviral therapy. Secondary objectives are to determine if \[18F\]F-AraG PET-MRI is able to detect differences in T cell activation between patients with early versus late treated HIV infection and to determine if \[18F\]F-AraG uptake correlates with direct blood and tissue measures of HIV reservoir size and activity in the above cohorts/studies.