Figure 3.

Lack of immunostimulatory activity of 2′-OMe–modified Dicer-substrate short-interfering RNAs (DsiRNAs). Mice were dosed once intravenously, at 10 mg/kg, with β-catenin DsiRNAs in lipid nanoparticle (LNP) F30.1, a formulation designed to facilitate immunostimulation. Seven days postdose, serum was analyzed for an immune response, indicated by antibody to PEG. The heavily 2′-OMe–modified DsiRNA β-cat-253-M14/M35 did not show significant in vivo immunostimulation activity, compared with mice treated with phosphate-buffered saline (PBS) or with LNP F30.1 without DsiRNA (Empty Particle (EP), dashed line), in contrast with DsiRNA β-cat-3393-M0/M11 with lower 2′-OMe modification (**P < 0.01, relative to EP; mean ± SEM).