FIGURE 4.

The binding of rFHR-5 to surface heparin is inhibited by fluid-phase preincubation with sulfated GAGs. (A) Binding of rFHR-5 (1.5 µg/ml) to surface heparin following preincubation with GAG polysaccharides (160µg/ml). (B) Binding of rFHR-5 (0.5 µg/ml) to surface heparin following preincubation with heparin oligosaccharides (160 µg/ml). Control represents surface binding of rFHR-5 in the absence of fluid-phase GAGs. The effect of ionic strength on the fluid-phase inhibition by heparin (160 µg/ml) of the surface binding of (C) FH (0.5 µg/ml), and (D) rFHR-5 (1.5 µg/ml) to immobilized heparin. The data are representative of two independently performed experiments. Data points represent mean of two replicates with SD.