Table 4.
Binding kinetics of C1q to Fc domain of IgG and DuetMab antibodiesa.
| Antibody | Antigen concentration (nM) | Apparent affinity |
||
|---|---|---|---|---|
| kon (M–1 sec–1) | koff (sec–1) | KD (µM) | ||
| QD6 IgG | 200 | (2.7 ± 0.63) × 105 | 2.9 ± 0.61 | 10.8 ± 0.45 |
| NMGC-QD6 DuetMab | 200 | (9.6 ± 0.43) × 105 | 2.4 ± 0.35 | 2.5 ± 0.62 |
| Trastuzumab IgG | 200 | (2.1 ± 0.23) × 104 | (1.9 ± 0.32) × 10–1 | 9.4 ± 0.27 |
| Trastuzumab/NMGC DuetMab | 200 | (8.9 ± 0.28) × 104 | (2.3 ± 0.33) × 10–1 | 2.6 ± 0.87 |
| Trastuzumab/NMGC DuetMab | 55 | (1.0 ± 0.23) × 105 | (1.8 ± 0.22) × 10–1 | 1.7 ± 0.44 |
aKinetic measurements to soluble C1q were performed with an Octet 384 instrument. Dissociation constants (KD) were calculated as the ratio of koff/kon from a nonlinear fit of the data.