Protective effects of anti-ricin A-chain RNA aptamer against ricin toxicity

Figure 1 Cell-free luciferase translation assay for biological activity of ricin and protective effects of anti-RTA 31RA aptamer. A: Effects of increasing concentrations of RTA on luciferase activity in cell-free translation assay (upper panel) and neutralization by 31RA aptamer (lower panel); B: Effects of increasing concentrations of ricin holoenzyme on luciferase activity in cell-free translation assay (upper panel) and neutralization by 31RA aptamer (lower panel).

Figure 2 Cell-based luciferase assay for biological activity of ricin in CHO AA8 cells. A: Kinetics of induction of luciferase activity in CHO AA8 cells and inhibition by ricin and anisomycin. CHO AA8 cells were cultured in medium containing doxycycline (Dox) to suppress luciferase expression. For induction of luciferase expression, medium containing Dox was removed and replaced with medium (untreated) or medium containing ricin (1 μg/mL) or anisomycin (10 μg/mL). At various timepoints (0, 3, 6, 12, 24 h) after treatment, luciferase activity was measured. Light output is expressed as RLU; B: Dose-dependent inhibition of luciferase activity by increasing concentrations of ricin or anisomycin as control.

Figure 3 Protective effects of polyclonal anti-dgA IgG and anti-RTA 31RA aptamer on ricin-inhibited luciferase activity. A: Protective effects of anti-dgA IgG against ricin-inhibited luciferase activity, but not anisomycin-inhibited luciferase activity; B: Protective effects of various concentrations of 31RA aptamer against ricin-inhibited luciferase activity.

Figure 4 Protective effects of polyclonal anti-dgA IgG and anti-RTA 31RA aptamer on ricin-induced cell cytotoxicity as measured by MTS assay. A: Protective effects of anti-dgA IgG against ricin-induced cytotoxicity, but not anisomycin-induced cytotoxicity; B: Protective effects of 31RA aptamer against ricin-induced cytotoxicity.