Figure 4: Wild-type PTP1B attenuates whereas dominant negative (C215S-PTP1B) potentiates IL-6-stimulated smooth muscle cells migration. Cells were transfected with control virus expressing enhanced green fluorescent protein (EGFP) or with virus expressing wild-type (WT-1B, Figure 4A)or dominant negative PTP1B (CS-1B, Figure 4B) at multiplicity of infection values of 1015 for 24 hours. After viruses were removed, cells were further incubated for 24 hours to allow time for PTP1B expression. Cells were then treated with 20ng/ml of interleukin-6 for 24 hours after wounding. Upper panels show the representative Western blot indicating the expression levels of PTP1B. Graphs show the migration distance (mean+SE) from three independent experiments before and after IL-6 treatment. Data are analyzed by using one-way ANOVA followed by post hoc test. **P<0.01, compared to control, ##P<0.01 compared to IL-6 alone.