Table 3.
A panel of 12 mAbs (B1-B12) that were selected for validation of PEG 4K induced precipitation assay. Their solubility related properties and sequence-based properties are summarized. The reported pI values were calculated using MOE2017 (Chemical computing group).
| mAb | Isotype | pI (calculated) | Solubility properties |
|---|---|---|---|
| B1 | IgG4 | 7.1 | Poor solubility; insoluble aggregates in high concentration solution, precipitation without salt |
| B2 | IgG4 | 8.3 | Salt-dependent solubility: concentrations > 60 mg/ml in PBS; < 10 mg/ml at C6 (salt free buffer) |
| B3 | IgG4 | 8.2 | Phase separation in the absence of salt or low salt |
| B4 | IgG4 | 7.6 | No solubility Issues observed |
| B5 | IgG4 | 8.2 | No solubility Issues observed |
| B6 | IgG4 | 7.1 | No solubility Issues observed |
| B7 | IgG4 | 8.4 | High molecular weight increase and particle formation at concentrations > 25 mg/mL of citrate condition |
| B8 | IgG4 | 4.9 | No solubility Issues observed |
| B9 | IgG4 | 7.6 | Insoluble aggregate, particle and cryoglobulin formation at concentrations > 50 mg/mL |
| B10 | IgG1 | 8 | No solubility Issues observed |
| B11 | IgG1 | 8.6 | No solubility Issues observed |
| B12 | IgG4 | 7.8 | Phase separation observed in the absence of salt |