Table 1.
Assessment of rFcRn binding to albumins and IgGs using MST analysis
| Ligand | rFcRn pH 6 KD, μM | Human FcRn pH 6 KD, μM | Mouse FcRn pH 6 KD, μM |
|---|---|---|---|
| Albumins | |||
| Rat | 11.6* | ∼1.1 (34) | SB (34) |
| Rabbit | 11.8* | ||
| Human | >100* | 4.6 (22); 5.2 (38) | ∼86 (72) |
| Human | WB (34, 36) | 1.1 (34) | WB (34) |
| Porcine | >100* | >50* | |
| Mouse | >100* | 0.8 (72) | 9.3 (72); SB (34) |
| Bovine | >100*; WB (36) | ||
| Sheep | >100* | ||
| Rhesus | WB (34) | ||
| IgGs | |||
| Rat | 1.8* | ∼0.45 (11) | |
| Rat IgG2a | 0.014 (75) | NB (75) | |
| Rabbit | 0.19* | SB (76) | SB (76) |
| Human | 0.63* | 0.70 (2) | 0.265 (10) |
| 0.03 (75) | 0.09 (75) | ||
| Human | 0.50 (3) | 2.35 (10) | 1.2 (72) |
| Human IgG1 | 0.63 (15) | 0.082 (15) | |
| Bovine | 1.5* | WB (76) | SB (76) |
| Mouse | >100* | WB (76) | ∼0.01 (72) |
| Mouse IgG1 | >50 (15) | 0.75 (15) | |
| Mouse IgG2a | 0.019 (75) | NB (75) | 0.025 (75) |
| Rat and mouse IgGs | ∼0.05 (5) | ||
Data shown are from the indicated references.
*
Data from the present study.
FcRn, neonatal Fc receptor; rFcRn, rat FcRn; MST, microscale thermophoresis; WB, weak binding; SB, strong binding; NB, no binding.