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Protein A chromatography increases monoclonal antibody aggregation rate during subsequent low pH virus inactivation hold.

Mazzer AR, Perraud X, Halley J, O'Hara J, Bracewell DG - J Chromatogr A (2015)

Bottom Line: Yet, a more limited set of evidence suggests that low pH may not be the sole cause of aggregation in protein A chromatography, rather, other facets of the process may contribute significantly.Similar experiments were implemented in the absence of a chromatography step, i.e. IgG4 aggregation at low pH.Rate constants for aggregation after protein A chromatography were considerably higher than those from low pH exposure alone; a distinct shift in aggregation rates was apparent across the pH range tested.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemical Engineering, University College London, Bernard Katz Building, Gordon Street, London WC1H 0AH, United Kingdom.

No MeSH data available.


Related in: MedlinePlus

Semi-log plot of monomer decay rate, R0, against pH in solution at three different IgG concentrations. Y-error bars show the standard error for the R0 parameter (Eq. (2)) obtained from least squares fitting; x-error bars represent pH measurement error. Linear regression was applied for concentrations 2.7 mg/mL and 4.5 mg/mL; for clarity, 95% confidence intervals only are shown for these fits. A trend has not been fitted to the 0.9 mg/mL data because there are few data points.
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fig0020: Semi-log plot of monomer decay rate, R0, against pH in solution at three different IgG concentrations. Y-error bars show the standard error for the R0 parameter (Eq. (2)) obtained from least squares fitting; x-error bars represent pH measurement error. Linear regression was applied for concentrations 2.7 mg/mL and 4.5 mg/mL; for clarity, 95% confidence intervals only are shown for these fits. A trend has not been fitted to the 0.9 mg/mL data because there are few data points.

Mentions: The value of interest resulting from fitting curves to the data is the rate constant, R0. The rate constant provides a convenient comparator for chromatography experiments, similarly to that used by Shukla et al. [9]. Rate constants varied most with pH, while IgG4 concentration had a limited effect on R0 values, within the concentration range tested, as seen in Fig. 4. To verify concentration effect, or lack thereof, R0 was plotted against pH for the three IgG concentrations tested and linear regression with 95% confidence limits was applied to each data set. There were few data points at 0.9 mg/mL so this data set was not fitted. Confidence intervals of the linear fits for 2.7 mg/mL and 4.5 mg/mL overlapped, indicating that IgG concentration did not significantly affect R0 in solution (Fig. 4). This is useful in terms of allowing some flexibility in IgG concentration for column experiments, as elution fractions may not be of precisely the same concentration for every run.


Protein A chromatography increases monoclonal antibody aggregation rate during subsequent low pH virus inactivation hold.

Mazzer AR, Perraud X, Halley J, O'Hara J, Bracewell DG - J Chromatogr A (2015)

Semi-log plot of monomer decay rate, R0, against pH in solution at three different IgG concentrations. Y-error bars show the standard error for the R0 parameter (Eq. (2)) obtained from least squares fitting; x-error bars represent pH measurement error. Linear regression was applied for concentrations 2.7 mg/mL and 4.5 mg/mL; for clarity, 95% confidence intervals only are shown for these fits. A trend has not been fitted to the 0.9 mg/mL data because there are few data points.
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4582070&req=5

fig0020: Semi-log plot of monomer decay rate, R0, against pH in solution at three different IgG concentrations. Y-error bars show the standard error for the R0 parameter (Eq. (2)) obtained from least squares fitting; x-error bars represent pH measurement error. Linear regression was applied for concentrations 2.7 mg/mL and 4.5 mg/mL; for clarity, 95% confidence intervals only are shown for these fits. A trend has not been fitted to the 0.9 mg/mL data because there are few data points.
Mentions: The value of interest resulting from fitting curves to the data is the rate constant, R0. The rate constant provides a convenient comparator for chromatography experiments, similarly to that used by Shukla et al. [9]. Rate constants varied most with pH, while IgG4 concentration had a limited effect on R0 values, within the concentration range tested, as seen in Fig. 4. To verify concentration effect, or lack thereof, R0 was plotted against pH for the three IgG concentrations tested and linear regression with 95% confidence limits was applied to each data set. There were few data points at 0.9 mg/mL so this data set was not fitted. Confidence intervals of the linear fits for 2.7 mg/mL and 4.5 mg/mL overlapped, indicating that IgG concentration did not significantly affect R0 in solution (Fig. 4). This is useful in terms of allowing some flexibility in IgG concentration for column experiments, as elution fractions may not be of precisely the same concentration for every run.

Bottom Line: Yet, a more limited set of evidence suggests that low pH may not be the sole cause of aggregation in protein A chromatography, rather, other facets of the process may contribute significantly.Similar experiments were implemented in the absence of a chromatography step, i.e. IgG4 aggregation at low pH.Rate constants for aggregation after protein A chromatography were considerably higher than those from low pH exposure alone; a distinct shift in aggregation rates was apparent across the pH range tested.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemical Engineering, University College London, Bernard Katz Building, Gordon Street, London WC1H 0AH, United Kingdom.

No MeSH data available.


Related in: MedlinePlus