Table 1

Scatchard analysis of 125I-labeled EGF binding to intact A431 cells in the presence of PD 153035a

High affinityLow affinityPlus PD 153035
nbKDcnKDnKD
Experiment 1: 100 nm10.0940.774.80.13
Experiment 2: 100 nm1.10.0860.89.00.26
Experiment 3: 200 nm10.097.70.769.70.15
  • a Binding parameters were determined from Scatchard plots to obtain receptor numbers per cell (n) and ligand dissociation constants (KD). 125I-labeled EGF binding was determined at 4°C for 1 h as described in “Materials and Methods.”

  • b × 105.

  • c nm.