Table 1. The kinetics parameters of PAI-1, PAI-1R76E, PAI-2, uPA and uPA–serpin complexes binding to VLDLr, measured by SPR.
aBinding data was fitted using the BIAevaluation 4.0 software. The binding model chosen represents that with the lowest φ2 value. Values are means±S.E.M., n=3.
| Analyte | Binding model | ka (M−1·s−1) | kd (S−1) | KDa (nM) | ϕ2 |
|---|---|---|---|---|---|
| PAI-1 | 1:1 | 9.90×104 (±6.83×104) | 4.17×10−3 (±1.19×10−3) | 51.8 (±21.9) | 8.12 |
| PAI-1R76E | No binding | − | − | − | − |
| PAI-2 | No binding | − | − | − | − |
| uPA | Heterologous analyte | 8.00×104 (±1.08×104) | 1.32×10−2 (±0.01×10−2) | 209 (±25.1) | 13.9 |
| 5.48×104 (±0.74×105) | 1.50×10−3 (±0.13× 0−3) | 31.2 (±5.69) | |||
| uPA–PAI-1 | Heterologous analyte | 1.50×105 (±0.20×105) | 1.30×10−2 (±0.10×10−2) | 84.8 (±1.69) | 19.6 |
| 1.00×105 (±0.40×104) | 1.30×10−4 (±0.18×10−3) | 1.51 (±0.27) | |||
| uPA–PAI-1R76E | 1:1 | 7.79×104 (±0.84×104) | 7.08×10−4 (±2.01×10−4) | 9.95 (±3.53) | 8.2 |
| uPA–PAI-2 | 1:1 | 1.73×105 (±0.62×105) | 5.61×10−4 (±0.98×10−4) | 4.68 (±0.90) | 1.9 |