Figure 1. Hydrodynamic tail vein injection of plasmid DNA transgenes in vivo produces expression mainly in the liver with rare expression in the kidney.

(a) Mice were injected with 20 μg of an enhanced firefly luciferase transposon driven by the promoter shown and imaged the following day to detect luciferase expression. The tissues were stained for luciferase (green) and nuclei by DAPI (blue). (b) Liver; faintly luciferase-positive cells are indicated by arrows. (c) Kidney; interstitial luciferase-positive cells are indicated by arrowheads and the glomerulus is marked by a dashed outline. (d) Co-staining in kidney with SLC3A1/rBAT to mark the proximal tubules (red). Representative of n = 3. Promoters used to express luciferase were: CMV (cytomegalovirus, constitutive viral), EF-1α (Elongation Factor-1 alpha, constitutive endogenous), γGT1 (Gamma-glutamyl transferase, tubule-specific), and podocin (podocyte-specific).