CCL21 mediates Ca²⁺ mobilization from intracellular stores. MoDCs stimulated with sCD40L and PGE2 were loaded with fluo-3-AM, and chemokine-induced Ca²⁺ mobilization was analyzed using flow cytometry (A). Experiments (B-D) were performed in Ca²⁺-free buffer in the presence of 2 mM EGTA. (C-D) The release of Ca²⁺ from intracellular stores was inhibited by the addition of the PLC inhibitor U73122 (10 μM). Baseline was established for 30 seconds before CCL21 (250 ng/mL) was added, as indicated by the arrow. Representative results obtained from MoDCs of a single donor are shown. At least 3 independent experiments with MoDCs from different donors gave similar results.