TABLE 1.

CR2 binding constants from NMR titrations and ITC

Shown are weak and upper limits to tight binding constants for CR2-ligand interactions determined using NMR titrations monitoring chemical shift changes. Also shown are CR2-ligand binding constants determined using ITC. UL, upper limit.

CR2 ligand	NMR determined, Kd	ITC determined, Kd
	μm	μm
C3d	Tight, UL 45	0.13 ± 0.05
	Weak 130 ± 60	160 ± 20
gp350	UL, 60	0.014 ± 0.009
IFN-α	UL, 70	0.036 ± 0.008