Fig. 1

Visualization and quantification of FDG uptake. a Ex vivo biodistribution 24 h after second RNA-lipoplex vaccination shows elevated FDG uptake predominantly within the spleen which is the organ with the second highest FDG uptake after myocardium. b, c Time course of elevated spleen metabolism after the second of two weekly RNA-lipoplex vaccinations FDG uptake returns to normal levels as early as after 72 h. Controls were injected with 0.9% saline. FDG uptake was quantified either by ex vivo biodistribution (b) or by in vivo PET imaging (c). d Visualization of time course of FDG uptake by axial PET/MR slices