The HBD within the A1 domain of VWF mediates GF binding. (A) The location of the A1 domain and HBD within VWF. (B-C) Affinity of VEGF-A, PlGF, PDGF-BB, FGF-2, or CXCL-12 against (B) recombinant VWF A1 domain protein or (C) VWF A1 HBD peptide. ELISA plates were coated with 10 µg/mL recombinant VWF A1 domain protein or 10 µg/mL VWF A1 HBD peptide and further incubated with a 1-μg/mL VEGF-A, PlGF, PDGF-BB, FGF-2, or CXCL-12 solution. Bound GF or chemokine was detected by using a specific antibody for each GF or chemokine (n = 4; data are mean ± SD). Analysis of variance (ANOVA) with Tukey’s test or Mann-Whitney U test was performed. *P < .05; **P < .01.