Thermodynamic analysis of VEGF-D interactions with VEGFR-2 and VEGFR-3. (A) Calorimetric titrations of the 4 VEGF-D (Cys117Ala) variants (D89-195, D92-195, D100-195, and D100-205) to the Fc-tagged VEGFR-2D23. (B) Titration of the 4 VEGF-D variants with VEGFR-3D17. (C) Summary of the enthalpy change (ΔH ± SD), entropy change (ΔS), binding affinities (Kd ± SD), and stoichiometry (n) of the ITC binding experiments. ND indicates not determinable.