Table 1.

Binding kinetic parameters and T_M of IGKV3-15*01 and all pH-responsive light chain variants binding to CEACAM5.

Antibody	pH 7.4			pH 6.0	pH 5.5	pH 5.0	Kdis ratio (pH 6.0) vs. IGKV3-15	Kdis ratio (pH 5.5) vs. IGKV3-15	Kdis ratio (pH 5.0) vs. IGKV3-15	Tm (°C) pH 7.4	Tm (°C) pH 6.0
	KD nM	Kon (×10−6) M−1 s−1	Kdis (×10−4) s−1	Kdis (×10−4) s−1	Kdis (×10−4) s−1	Kdis (×10−4) s−1
IGKV3-15*01	0.90	0.264	2.38	3.68	6.63	8.71	1	1	1	66.5 ± 0.7	65.0 ± 0.5
K39	4.16	0.238	9.89	50.7	156	353	14	24	41	66.7 ± 0.3	65.3 ± 0.3
K40	3.12	0.245	7.65	37.6	121	437	10	18	50	66.5 ± 0.0	65.3 ± 0.8
CV1	4.11	0.235	9.68	45.4	176	416	12	27	48	66.5 ± 0.5	65.0 ± 0.5
CV2	4.14	0.279	11.5	55.5	167	450	15	25	52	66.5 ± 0.5	64.8 ± 0.4
CV3	2.55	0.249	6.36	40.4	152	447	11	23	51	66.8 ± 0.3	65.3 ± 0.3

The binding affinity is listed for association and dissociation at pH 7.4 with both k_on and k_off. The k_off values for the different dissociation pH-values are also listed. The ratios of the dissociation constant at pH values <7.4 in comparison to k_dis at pH 7.4 are shown on the right together with the dissociation ratios under the same conditions.