Figure 5.

INF-γ–independent effects of TLR3 ligands on cultured cells. A: Serum-deprived cells were incubated for 30 minutes (for phospho-protein detection) or for 24 hours (for caspase-8 detection) with poly(I:C), NRP1 siRNA, or NT siRNA, as indicated. Cell lysates were analyzed by Western blot with phospho-site specific or anti–caspase-8 antibodies. β-actin was used as loading control. Results shown are representative of three independent experiments. B: Cells were grown in the presence of various concentrations of INF-γ, poly(I:C), or NT siRNA for 48 hours and cell viability and growth over time was estimated using MTT assay. Results are expressed as percentage of viable cells observed in cell cultures grown in the absence of inhibitors. Data are representative of three independent experiments. C: HUVECs were cultured on collagen gels in starvation medium (M199 medium containing 1% FBS) alone or supplemented with 100 ng/ml INF-γ, 50 μg/ml poly(I:C), or 50 μg/ml of NT siRNA. Photographs were taken at 24 hours. Scale bar, 100 μm. The total tube length and the tubular network area were quantified using Histolab software. Results shown are representative of four independent experiments. *P < 0.05; **P < 0.01; ***P < 0.001. Student’s t-test).