WASP knockdown Jurkat T cells are impaired in chemotaxis towards SDF-1α. A) Jurkat T cells were transduced with retrovirus expressing human WASP specific shRNA and EGFP. The cells were FACS sorted and the efficiency of knock down was determined by western blot using anti-WASP and anti-GAPDH antibody. B) WASP mRNA levels in Jurkat T cells and JurkatWASP-KD T cells were quantified by real-time PCR. ***P < 0.001 compared to WT Jurkat T cells. C) Vector plots of migration paths of 20 randomly chosen cells from WT Jurkat T cells or JurkatWASP-KD T cells exposed to a gradient of SDF-1α in the Dunn chamber. The starting point of each cell is at the intersection of the X and Y axes. The source of SDF-1α was at the top. D) Migration velocity of WT and JurkatWASP-KD T cells shown as the mean of the velocities of 60 randomly chosen cells (20 cells each from 3 sets of experiments) *p < 0.05. E) Circular histograms showing the percentage of cells at the final positions in each of the sectors (20°). The source of SDF-1α was at the top. F) Transwell migration assay was performed with WT Jurkat T cells and JurkatWASP-KD T cells. 2 X 105 cells were loaded in upper well and allowed to migrate towards SDF-1α (100 ng/ml) containing media in the lower well for 3.0 hrs. Cells migrated to the lower well were counted and plotted as percentages of total cells added to the upper well. Data represent the mean of three independent experiments. **p < 0.01 compared to WT Jurkat T cells.