Fig. 4

In vitro gene silencing. a Negative control siRNA (NC-siRNA) or b siRNA for luciferase genes (at 50, 100, or 200 nM) were mixed with respective ELPs. 4T1-luc cells were transfected with siRNA/ELPs complexes for 3 h and checked for luciferase gene silencing after 48 h of transfection using an IVIS. Results are presented as the means ± SDs of three separate experiments performed in triplicate. A t-test was performed to determine the significance of various groups after siRNA/ELPs complex treatments with different concentration of siRNA (50, 100, 200 nM). *P < 0.05, Control versus lipofectamine mediated siRNA (200 nM) delivery and **P < 0.001, Control versus siRNA/Tat-A₄V₈₄ mediated siRNA (200 nM) delivery. c 4T1 cells were transfected with siRNA/ELP variant complexes for 3 h and harvested at 48 h after transfection. Later cell lysates were western blotted to assess luciferase gene silencing. d The histogram of normalized luciferase band intensities obtained using image J software. **P < 0.001 (Student’s t-test), significant difference for Tat-A₁E₂₈ or Tat-A₄V₈₄ compared with control