Chemotaxis of murine and human cell lines to SDF-1 and MS-5 supernatant. Several cell lines were tested for their ability to migrate in transwell assays in response to SDF-1 (100 ng/mL) and MS-5 supernatant (undiluted). The number of cells that migrated to SDF-1 or MS-5 was divided by the number of background cells (cells that migrated to medium alone) to determine the chemotactic index, for panels A, B, and D. In panel C, the percentage of migrating cells is shown for comparison. In some columns, the standard deviations were too small to be visualized. Similarly, the chemotactic index of transformed K562 cells migrating to MS-5 supernatant and SDF-1 was below 1.0. Standard er- ror bars for the cell lines Ba/F3.p185^BCR/ABL, Mo7e, Mo7e.p210^BCR/ABL, K562, 32D.p210^BCR/ABL, and 32D.p185^BCR/ABL are calculated from triplicate values in single migration experiments, whereas the error bars for Ba/F3 and Ba/F3.p210^BCR/ABL cells were calculated from data obtained in 6 and 4 migration experiments, respectively. In panel C, Ba/F3 cells transformed with p210 were tested and data from 4 migration experiments (2 per cell line) were pooled.