Effect of PF-4±derived peptides on binding of¹²⁵I-VEGF to endothelial cells. LEII cells or ACE cells are incubated with 5 ng/mL ¹²⁵I-VEGF in the presence or absence of 500 ng/mL unlabeled ligand (nonspecific binding, NS), or PF-4–derived peptides. Binding experiments are performed as indicated in Materials and Methods. Binding experiments on LEII cells with 10 μmol/L of indicated peptides (A) or increasing concentrations (B) of peptide 47-70; binding experiments on ACE cells with fixed (10 μmol/L) concentrations (C) of the different peptides or increasing concentrations (D) of peptide 47-70. Results are expressed as the mean ± SD of experiments done in duplicates.