FIG 4.

Efficient chemotactic and endothelial migration of P. gingivalis-infected MoDCs toward CXCL12 but not CCL19. After 24 h of treatment as indicated, MoDCs were migrated through a filter using a Boyden chamber to determine relative MoDC migration distance (A, B, C) or through transwell inserts to determine the number of MoDCs undergoing transendothelial migration (D) in response to either the CXCR4 ligand CXCL12 or the CCR7 ligand CCL19. (A to C) MoDCs (1 × 10⁵/well) were loaded in triplicate into the top chamber of a microchemotaxis chamber and migrated through a nitrocellulose membrane toward a CCL19 or CXCL12 chemokine gradient. (A) P. gingivalis-infected MoDCs do not actively migrate to the 100-ng/ml CCL19 gradient. Only the MoDCs treated with the inflammatory cocktail migrated toward the CCL19 significantly compared to untreated MoDCs. (B) MoDCs infected with live WT Pg381 show a significant increase in migration to CXCL12 over migration of untreated MoDCs at a low concentration. With an increased concentration of CXCL12, MoDCs infected with heat-killed Pg381 show significant increases in migration toward CXCL12, but migration of MoDCs treated with live Pg381 is still significantly higher. (C) The chemical inhibitor of CXCR4, AMD3100, was incubated with MoDCs for 1 h prior to migration. Treatments with AMD3100 completely abrogated MoDCs' migration in response to CXCL12. (D) Pg381-infected MoDCs (1 × 10⁵/well) were migrated through a monolayer of ITECs in response to 100 ng/ml of either CXCL12 or CCL19 in the bottom compartment of the transwell inserts. Only infected MoDCs responding to CXCL12 were able to significantly migrate through the endothelial barrier. *, P < 0.01.