Effect of different competitors on the binding of uPA/suPAR-complex to LM-TK⁻ cells. MoAb-13H1 against VN (•), multimeric VN (○), monomeric VN (▴), an MoAb against thrombospondin-1 (□), or soluble thrombospondin-1 (▪) were tested for their effect on the binding of the uPA/suPAR-complex to LM-TK⁻ cells. Data are expressed as percentage of control (mean ± SEM) from three different experiments. The binding of¹²⁵I-Gly158scuPA in the presence of suPAR and in the absence of any competitor served as the 100% control, and the binding of ¹²⁵I-Gly158scuPA alone was about 20% of the binding of the complex.