Deletion of Cdc42 has no effect on B-cell migration or migration-related signaling pathways. (A) The migration of B cells from WT and Cdc42^−/− (KO) mice toward SDF-1 and BLC was examined in a transwell assay. The number of cells that migrated to the exterior of the transwell chamber was normalized to the total number of cells added to the interior of the chamber. Data are means ± SD. (B) Purified B cells were incubated in B-cell culture medium at 37°C for 2 hours, and then stimulated for 3 minutes with 100 ng/mL SDF-1 or 200 nM BLC. Stimulation was stopped by adding cold phosphate-buffered saline, and the cells were subjected to Western blot analysis.