Carryover Studiesa
| Species | Chromatography Parameter Conditions1 | Load Control (log10 CFU)b | Flow-through Burden (log10 CFU) | Salt Wash Burden (log10 CFU) | Elution LRVc | Carryover (CFU/mL) |
|---|---|---|---|---|---|---|
| A. laidlawii | Best case | 7.3 ± 0.1 | 6.9 ± 0.1 | 4.7 ± 0.1 | 5.9 ± 0.3 | <10 |
| Center point | 7.1 ± 0.2 | 6.7 ± 0.1 | 4.2 ± 0.4 | 4.7 ± 0.4 | <10 | |
| Worst case | 7.3 ± 0.1 | 6.9 ± 0.1 | 4.3 ± 0.1 | 3.3 ± 0.2 | 25 | |
| M. orale | Best case | 8.0 | 7.8 | 5.5 | 4.0 | 700 |
| Center point | 7.3 ± 0.1 | 7.1 ± 0.2 | 5.1 ± 0.2 | 4.3 ± 0.9 | 1.9 × 103 | |
| Worst case | 7.5 ± 0.4 | 7.5 ± 0.4 | 5.1 ± 0.9 | 3.2 ± 1.2 | 2.5 × 103 | |
| Medium Column Worst case | 8.4 ± 0.1 | 7.6 ± 0.5 | 5.9 ± 0.5 | 2.8 ± 0.1 | 1.5 × 104 | |
| M. arginini | Center point | 7.9 ± 0.3 | 7.7 ± 0.1 | 5.2 ± 0.4 | 5.0 ± 0.4 | 105 |
| Worst case | 7.6 ± 0.5 | 7.5 ± 0.5 | 4.4 ± 0.5 | 3.3 ± 0.4 | 205 |
↵a Mycoplasma burden in input (load control), output (eluate), as well as flow-through and salt wash fractions were collected and measured for titer. Log reduction value (LRV) was calculated from the mycoplasma burden in the elution fractions. Carryover was measured from early effluent from a second cycle1. Best case was performed once as proof of concept for M. orale because the focus of these studies was to identify the conditions that would have poor mycoplasma clearance. Only center point and worst-case experiments were performed with M. arginini because of its higher LRVs compared to M. orale. Adapted from Wang et al., 2017, with permission.
↵b CFU is colony-forming units.
↵c LRV is log reduction value.