FIGURE 4.
2′-F modified siRNA inhibits gene expression in living mice. Representative bioluminescence images of light emitted from living mice transfected, 2 d earlier, with the luciferase expression plasmids pGL3-control. Mice (N = 4–5 mice per group) received pGL3-control alone (A) or were cotransfected with (B) 2′-OH GL3 siRNA, (C) 2′-OH GL3 siRNA and the RNase inhibitor, RNasin, (D) 2′-F GL3 siRNA, (E) 2′-F inverted GL2 siRNA. The mouse in panel F received a low pressure i.v. injection of 2′-F GL3 siRNA on day 1 to test if stabilized siRNAs could be taken up by the liver without hydrodynamic transfection. Mice in panels B, C, and D show significant reductions in emitted light as a result of RNA. Hydrodynamic transfection with 2′-F inverted GL2 siRNA and low pressure i.v. transfection of 2′-F GL3 siRNA did not result in significant RNAi.