Fig. 6.

Ca²⁺ dependence of ligand binding to human and bovine mincle. Binding of ¹²⁵I-mannose-BSA to the biotin-tagged CRDs immobilized in streptavidin-coated wells was quantified for (A) the CRD from human mincle and (B) the CRD from bovine mincle. Binding was conducted for 2 h in the presence of 150 mM NaCl and 25 mM Tris–Cl, pH 7.8 at 4°C. Following incubation with ligand, wells were washed 3× with buffer containing 150 mM NaCl, 25 mM Tris–Cl, pH 7.8, and 25 mM CaCl₂. The experimental data, shown as black spheres, were fitted to first- and second-order binding equations, shown respectively as blue and green lines, using a nonlinear least-squares fitting program.