Figure 3.

Transcriptional activity of short regulatory elements and promoters (P) in transfected human endothelial hCMEC/D3 cells. (a) Schematic representation of the investigated DNA constructs. For short regulatory elements, we used the CMV enhancer (C) in all constructs as well as the short Tie2 intron (S) and the WPRE (W) as indicated. (b and c) Rate of eGFP-positive hCMEC/D3 cells transfected with plasmids containing different regulatory sequences. Five days after transfection, cells were immunostained for eGFP. Data are presented as mean ± SD and were analyzed by two-way ANOVA (short regulatory element F(3/160)=171, p < 0.0001; promoter F(7/160)=151.9, p < 0.0001; interaction F(21/160)=34.34, p < 0.0001), ns not significant, *p < 0.0332, **p < 0.0021, ****p < 0.0001 (Tukey’s multiple comparison test, n = 6 transfected wells per plasmid). (d) Representative images of hCMEC/D3 cells transfected with plasmids expressing eGFP under the regulation of the synthetic promoter sequences CAG, S-C-Cdh5-W, C-Ocln-W, C-Slc2a1-S-W and C-Slco1c1-W. The images were stained for eGFP (green) and DNA (blue). Scale bar, 100 µm.