Endostatin is an endogenous inhibitor of angiogenesis. Although several endothelial cell
surface molecules have been reported to interact with endostatin, its molecular mechanism
of action is not fully elucidated. We used surface plasmon resonance assays to characterize
interactions between endostatin, integrins, and heparin/heparan sulfate. α5β1 and αvβ3
integrins form stable complexes with immobilized endostatin (KD=∼ 1.8× 10− 8 m, two-state
model). Two arginine residues (Arg 27 and Arg 139) are crucial for the binding of endostatin …