TABLE 1.

SPR-derived affinities of the interaction of scFv-Fc variants with FcRn

scFc-Fc variant	mFcRn KD1	mFcRn KD2	hFcRn KD1	hFcRn KD2
	nm	nm	nm	nm
WT	0.2 ± 0.0	43.8 ± 2.7	6.4 ± 2.6	105.3 ± 64
H435R	1.8 ± 0.1	122.1 ± 55.8	9.4 ± 0.7	196.6 ± 19.3
H435Q	80.9 ± 18.1	400.1 ± 112.8	NDa	ND
I253A	443.5 ± 4.9	1054 ± 1.9	ND	ND
H310A	ND	ND	ND	ND
H310A/H435Q	ND	ND	ND	ND

^a ND mean not determined because of no binding or very weak binding.