TABLE 3.
Endotoxin levels in purified VHH preparations
| VHH | Mean LPS content (EU/ml)a ± SEM |
|---|---|
| N1-3-VHHm | 0.094 ± 0.007 |
| N1-5-VHHm | 0.096 ± 0.017 |
| N1-7-VHHm | 0.095 ± 0.012 |
| SA-VHHm | 0.094 ± 0.008 |
| N1-3-VHHb | 0.092 ± 0.005 |
| N1-5-VHHb | 0.093 ± 0.007 |
| BL-VHHb | 0.107 ± 0.024 |
| N1-3-VHH-Fc | 0.100 ± 0.020 |
| N1-5-VHH-Fc | 0.103 ± 0.019 |
| N1-7-VHH-Fc | 0.076 ± 0.011 |
| GP4-Fc | 0.100 ± 0.016 |
| PBS | 0.07 ± 0.015 |
a
The endotoxin (lipopolysaccharide [LPS]) levels (endotoxin units [EU]) in purified, E. coli-derived (VHHm/b) and A. thaliana-derived (VHH-Fc and GP4-Fc) proteins were determined by a Limulus amebocyte lysate-based chromogenic test and calculated relative to an endotoxin standard.