Table 2.

Receptor binding properties of dimeric and monomeric forms of IL5 from titration calorimetry

IL-5 construct	Molar ratio (IL5/receptor)	Kd, nM	ΔG, kcal/mol	ΔH, kcal/mol	−TΔS (kcal/mol)
wtIL5	0.72	14	−10.9  ± 0.6	−17.5  ± 0.6	6.6  ± 0.8
DABC	0.61	190	−9.3  ± 0.6	−17.7  ± 3.0	8.4  ± 3.1
GM1	0.60	220	−9.2  ± 0.6	−19.2  ± 3.0	10  ± 3.1

Error in K_d’s values is about a factor 2-3. Conditions are as follows: 10 mM NaPO₄, and 150 mM NaCl (pH 7.4 at 30°C).