Table 1.

Summary of binding parameters k_on (1/M s), k_off (1/s) and K_d (M). The K_d reported is the ratio k_off / k_on.

Fc receptor	variant	kon	koff	Kd
FcRn	WT	4.4 × 104	2.2 × 10−3	5.1 × 10−8
	QA	3.8 × 104	3.5 × 10−3	9.3 × 10−8
	FA	4.6 × 104	2.2 × 10−3	4.7 × 10−8
FcγRI	WT	5.0 × 105	2.2 × 10−4	4.4 × 10−10
	QA	3.1 × 105	7.3 × 10−4	2.0 × 10−9
	FA	4.9 × 105	3.3 × 10−4	6.9 × 10−10
FcγRIIa	WT	1.1 × 106	2.9 × 10−1	2.7 × 10−7
	QA	7.7 × 105	3.0 × 10−1	3.9 × 10−7
	FA	-	-	-
FcγRIIIa	WT	4.6 × 105	5.0 × 10−2	1.1 × 10−7
	QA	2.8 × 105	2.0 × 10−1	6.1 × 10−7
	FA	4.1 × 105	4.3 × 10−1	1.0 × 10−6
FcγRIIIb	WT	4.3 × 105	7.1 × 10−1	1.6 × 10−6
	QA	6.3 × 104	5.2 × 10−1	8.3 × 10−6
	FA	-	-	-