Figure 6.

UNbC5-1 binds and inhibits C5 variant R885H.A and B, binding of Ecu-mab (A) and UNbC5-1 (B) to C5 WT and C5 R885H, using C5 WT- or C5 R885H-coated microtiter plates, incubated with increasing concentrations of Ecu-mab or UNbC5-1. Binding was assessed with a monoclonal anti-human-kappa antibody (A) or polyclonal rabbit-anti-VHH QE19 antibodies (B) and donkey-anti-rabbit-HRP secondary antibodies (A and B) at A450. C and D, CP mediated hemolysis of antibody-coated sheep erythrocytes incubated with 2.5% C5-depleted human serum and repleted with physiological concentrations of C5 WT or C5 R885H and a titration of Ecu-mab (C) or UNbC5-1 (D). The A₄₅₀ values of the supernatants were measured, and the % erythrocyte lysis was calculated using a 0% (buffer) and 100% (milliQ water) control sample. Data information: (A and D), data represent mean ± SD of three individual experiments and curves were fitted. CP, classical pathway.