Effect of stoichiometric titration of the light chain with inhibitors MU, RI, MS, and MoAb CLB-CAg A IgGs on fIXa binding. (A) Association of fIXa-DEGR (1,000 nmol/L) with light chain (35 fmol/mm2) in the presence of 0, 14, 24, 31, 38, 46, and 52 fmol/mm2 bound RI IgG is shown in curves 1 through 7, respectively. The resonance response curves recorded upon addition of fIXa-DEGR were corrected by subtraction of the resonance signal produced by bound IgG, and therefore the curves show the resonance signals solely produced by binding of fIXa to immobilized light chain (curve 1) or to IgG/light chain complexes (curves 2 through 7). (B) Binding of fIXa in the presence of MoAb CLB-CAg A IgG (○) or inhibitor IgG from MU (•), RI (▴), or MS (▵) prebound to immobilized light chain at the indicated molar ratio was determined from the equilibrium binding of fIXa-DEGR in the presence of each IgG as in (A).
