LEGEND FOR POZNANSKY VIDEO
Time-lapse digital video of T cells migrating in response to gradients of SDF-1α. (See QuickTime AVI video clip below). Sorted human peripheral blood CD4+ T cells are shown moving in response to medium alone, and gradients are shown in three QuickTime video clips entitled “Medium alone CD4+ T cells,” “SDF-1 (100 ng/ml) chemotaxis CD4+ T cells,” and “SDF-1 (10 µg/ml) fugetaxis CD4+ T cells.” Directional movement of cells toward 100 ng/ml of SDF-1 and away from 10 µg/ml of SDF-1 is shown. Minimal T cell movement was observed in the presence of medium alone. The SDF-1 was added by micropipette at the left margin of the screen. The location and relative concentration of SDF-1 is indicated by the blue gradient. There is a shift from low (×40) to high (×200) magnification in the second and third video clips. Some cells in the clip entitled “SDF-1 (10 µg/ml) fugetaxis CD4+ T cells” do not move under these conditions (see cell marked with a yellow arrow).