Figure 4.

B cell migrate toward homing chemokines and attract T cells in vitro. (A) Unstimulated CD19⁺ B cells (gray columns) and CD40B cells (black columns) were tested for migration toward CCL21, CXCL12, and CXCL13. CD40B medium alone was used to record spontaneous migration (NC). Cells were allowed to migrate for 3 h through a 5 μm filter transwell assay. (B) Purified CD4⁺ T cells were allowed to migrate for 2 h through a 5 μm filter to the lower chamber of transwell plates containing supernatant from murine CD40B cells, the chemokine CXCL12 (SDF1a) or CD40B medium alone (NC). Mean values ± SD from 3 experiments are shown. * p < 0.05, ** p < 0.01.