Figure 6

MPLA-activated tDCs acquire secondary lymphoid homing capacity in response to CCR7 and CXCR4 ligands compared to non-activated tDCs. MPLA activation of tDCs induces upregulation of migratory receptors CCR7 and CXCR4 and enhances chemotactic responsiveness to their ligands CCL19 and CXCL12. MPLA was added 24 hours before cell harvest to induce tDCs activation, generating MPLA-tDCs. After cell collection on day 5, DCs chemokine receptors expression profile was evaluated by flow cytometry together with their migratory response to relevant chemokines. tDCs without MPLA activation, mature (mDCs) and immature controls (iDCs) were also studied. (A) Representative density plots for each chemokine among CD11c + DCs (left). Data are also shown as the mean ± SD percentage of CD11c + DCs expressing the respective receptor analyzed from 10 independent experiments (right). (B) DC migratory capacity in response to 250 ng/ml of CCL19, CXCL12 or CCL5, or to medium alone, was assessed through a transwell assay. DC migration for each chemokine is expressed as the mean ± SD of migration index (Migrating DCs towards chemokine/Migrating DCs towards medium) determined in duplicates in 6 independent experiments (* P < 0.05; ** P < 0.01; *** P < 0.001).