Activin A induces DC migration and MMP-2, -3, and MMP-9 activation. (A) Dose-dependent migration of monocyte-derived DCs (Mo-DC) was evaluated using modified Boyden chambers. The right panel shows the migration in response to an optimal concentration of CCL3 (100 ng/mL; iDC = immature DC) or CCL19 (100 ng/mL; mDC = mature DC). Maturation of DC was achieved after incubation with 100 g/mL LPS for 24 hours. (B,C) Blood myeloid (M-DC) and plasmacytoid (P-DC) DC subsets were isolated and tested for their migration in response to activin A or to an optimal concentration (100 ng/mL) of CCL3 (M-DC) or CXCL12 (P-DC). Values represent the mean plus or minus SD of 7 (A) or 3 (B,C) different experiments performed with independent donors. (D) DCs were stimulated with 100 ng/mL activin A for 48 hours. MMP-2, MMP-3, and MMP-9 activity was evaluated by gelatin zymography. Band intensity of the bands was analyzed by Scion Image program. Results represent the average values of 2 independent experiments. *P < .05 by paired Student t test versus control group.