Table 2.
The kinetics of the affinity of IGFBP-1 for IGF-I assessed in triplicate by Biacore analysis for CM in hypoxia (1% O2) and leucine-deprived (450 μm leucine) samples relative to controls (incubator air, 20% O2 and 450 μm leucine)
| Samples | Ka (1/msec) | KD (1/sec) | KA (1/m) | KD (m) |
|---|---|---|---|---|
| Incubator air | ||||
| Mean | 4.89E+03 | 7.46E−04 | 6.57E+06 | 1.54E−07 |
| sd | 1.00E+01 | 1.05E−06 | 2.52E+04 | 1.00E−09 |
| Hypoxia | ||||
| Mean | 5.09E+03 | 2.97E−06 | 1.73E+09 | 5.83E−10 |
| sd | 1.00E+01 | 1.00E−08 | 1.00E+07 | 2.00E−12 |
| Dephosphorylated | ||||
| Mean | 1.50E+03 | 1.05E−03 | 1.38E+06 | 7.09E−07 |
| sd | 5.86E+00 | 4.16E−05 | 1.22E+03 | 1.29E−08 |
| 450 μm Leucine | ||||
| Mean | 7.64E+02 | 1.05E−03 | 6.50E+05 | 1.40E−07 |
| sd | 2.65E+00 | 5.03E−05 | 9.47E+04 | 4.93E−08 |
| 0 μm Leucine | ||||
| Mean | 1.56E+05 | 9.98E−04 | 1.57E+08 | 6.40E−09 |
| sd | 4.04E+02 | 1.80E−06 | 2.89E+05 | 5.7735E−12 |
| Dephosphorylated | ||||
| Mean | 2.43E+03 | 1.13E−03 | 1.08E+06 | 4.56E−07 |
| sd | 2.50E+01 | 2.00E−05 | 1.00E+01 | 7.21E−09 |
CM from hypoxic or leucine-deprived conditions were dephosphorylated by AKP and the kinetics reassessed. E, Times 10 to the power.