Figure 4.
sHLA-G1 does not interfere with VEGF receptors. (A) HUVECs were incubated with 125I-sHLA-G1 (2 ng/mL [50 pM]) in the absence (-) or presence of cold VEGF (1 μg/mL), FGF2 (1 μg/mL), or sHLA-G1 (sG1, 0.1, 1.0, or 10 μg/mL). Unlabeled sG1, but not VEGF or FGF2, prevented 125I-sHLA-G1 binding. (B) HUVECs were incubated with 125I-VEGF (2 ng/mL) in the presence of cold sG1, FGF2, or VEGF. Unlike cold VEGF, cold sG1 did not abrogate iodinated VEGF binding. In these conditions, the IC50 of cold ligands was 200 pM for VEGF and 2500 pM for sHLA-G1. Results are mean ± SEM of triplicate wells and are representative of 3 independent experiments.