Fig. 2.

Viability of U373MG cells treated with 2′-F-siRNA swarms. U373MG cells were transfected with the indicated siRNA swarms at the concentration range of 12.5–100 nM. The antisense strand of the modified siRNA swarms was fully (referred to as 100%) or partially (referred to as 10%) modified containing either 2′-F-dAMP, 2′-F-dCMP or 2′-F-dUMP as the modified nucleotide (10% or 100% F-A, F–C or F–U, respectively). 88-bp-long phi6-derived dsRNA with known cytotoxicity was used as a control RNA, at a concentration of 10 nM. The viability of the cells was quantified at 48 hpt and shown as relative viability compared to mock- and untreated samples. The error bars represent the standard deviation of the mean from two separate experiments with 3–5 biological replicates each. Significant difference to the unmodified UL29-specific swarm is marked with asterisks (*: p ≤ 0.05, **: p ≤ 0.01, ***: p ≤ 0.001).