FIG. 4.

VEGF-A guides VEGFR-positive cells in vitro. (A) Scheme of a well in which several concentrations of ligand-containing gel were placed in the corners. (B) VEGFR-positive cells migrated to gels containing 0, 10, 40, and 100 ng of VEGF-A/ml after 16 h of culture. (C) Numbers of cells that migrated to VEGF-A in medium containing DMSO as a negative control or 10 μM SU5416, a VEGFR kinase-specific inhibitor. VEGF-A at 40 ng/ml was most effective, and SU5416 completely suppressed this migration. PlGF or VEGF-E at 40 ng/ml also induced maximum migration. *, P < 0.05 by a t test.