Table 1.

The binding and blocking characteristics of anti-human VEGFR-1 antibodies

CloneKinetics of anti-VEGFR-1 antibodies*
Binding activity (ED50, nmol/L)Blocking activity (IC50, nmol/L)
Kon 105 M−1 s−1Koff 10−5 s−1KD 10−11 M
6F911.1 ± 1.267.38 ± 2.016.9 ± 0.360.145 ± 0.03VEGF-A: 1.05 ± 0.03
VEGF-B: ND
PlGF: 0.81 ± 0.05
13G129.58 ± 1.6311.05 ± 3.0612.4 ± 0.530.303 ± 0.02VEGF-A: 0.99 ± 0.02
VEGF-B: ND
PlGF: 0.73 ± 0.04
15F1110.16 ± 2.847.16 ± 2.217.0 ± 0.230.304 ± 0.01VEGF-A: 0.82 ± 0.03
VEGF-B: ND
PlGF: 0.48 ± 0.01
IMC-18F18.1 ± 2.44.29 ± 1.055.4 ± 0.30.112 ± 0.04VEGF-A: 1.04 ± 0.01
VEGF-B: 0.43 ± 0.01
PlGF: 0.38 ± 0.02
  • Abbreviation: ND, not determined.

  • * The values of kinetics of the antibodies were calculated from the data determined by BIAcore analysis.

  • The ED50 and IC50 values were calculated from the data analyzed using GraphPad Prism software. Binding activity was determined by measuring ability of the antibodies from binding to recombinant human VEGFR-1 in ELISA. Blocking activity was determined by measuring ability of the antibodies preventing recombinant human VEGFR-1 from binding to VEGF-A, VEGF-B, or PlGF in ELISA.