Formation of cord-like structures and migration of HDLECs are increased by inhibition of TGF-β signaling. (A) Total lengths of cord-like structures of HDLECs in three-dimensional culture were quantified. Cells were mixed with type I collagen gel at a density of 104 cells/well and seeded onto culture-slide wells. HDLECs were treated with TGF-β1 (1 ng/mL) or TβR-I inhibitor (3 μM). Formation of cord-like structures was observed by video microscopy, and total lengths of cord-like structures of cells were quantified 3 days after cultivation. Error bars represent SD (*P < .05, **P < .01). Effects of TGF-β signaling on migration of HDLECs were determined by Boyden chamber assay. Cells were seeded at 4 × 104 cells/well in the upper chambers coated with type I collagen. (B) Medium containing VEGF-C (50 ng/mL) was placed in the lower chamber, whereas that in the upper chamber did not contain VEGF-C but did contain TGF-β1 (1 ng/mL) or TβR-I inhibitor (3 μM). Migration of cells was determined after 6 hours. Bars represent 100 μm. (C) Migration of HDLECs was quantified. Cells that had migrated to the lower chambers were counted after 6 hours in triplicate. Error bars represent SD (*P < .05, **P < .01).
