Figure 5.

Comparative kinetic analysis of the interaction of serum C1q with LRP1 clusters II and IV. SPR analysis of LRP1 clusters II and IV interactions with serum C1q in two configurations. Top panels, clusters II and IV were injected over immobilized serum C1q (14,000 RU), (A, B) respectively. Bottom panels, serum C1q was injected over immobilized clusters II (1,230 RU) and IV (1,270 RU), (C, D) respectively. All injection were performed in 50 mM Tris, 150 mM NaCl, 2 mM CaCl₂, 0.05% P20, pH 7.4. The concentration of soluble ligands is indicated on each curve. The Req versus concentration plots of steady state fittings are shown on the top right of the SPR curves. K_D values (means ± SD) for each kinetics are summarized in Table 2.