Fig. 6.

Collagen V inhibits angiogenesis. HUVEC were layered onto an ECM, as described in Subjects and Methods, and medium was then added in the presence of increasing concentrations of the respective collagens. A–C, Micrographs show the extent of endothelial cell branching after 10 h incubation alone (A) or with the addition of collagen I (B) and collagen V (C) at 10 μg/ml. Magnification, ×200; bar, 125 μm. D, Quantification of the branch points from the addition of increasing concentrations of collagen V. E, Collagen I, III, and V were added to the ECM at a concentration of 10 μg/ml, followed by incubation for 10 h and counting of branch points. *, P < 0.05 vs. control; ***, P < 0.01 vs. control.