Effect of ambient light on monoclonal antibody product quality during small‐scale mammalian cell culture process in clear glass bioreactors

Abstract

During a small-scale cell culture process producing a monoclonal antibody, a larger than expected difference was observed in the charge variants profile of the harvested cell culture fluid (HCCF) between the 2 L and larger scales (e.g., 400 L and 12 kL). Small-scale studies performed at the 2 L scale consistently showed an increase in acidic species when compared with the material made at larger scale. Since the 2 L bioreactors were made of clear transparent glass while the larger scale reactors are made of stainless steel, the effect of ambient laboratory light on cell culture process in 2 L bioreactors as well as handling the HCCF was carefully evaluated. Photoreactions in the 2 L glass bioreactors including light mediated increase in acidic variants in HCCF and formulation buffers were identified and carefully analyzed. While the acidic variants comprised of a mixture of sialylated, reduced disulfide, crosslinked (nonreducible), glycated, and deamidated forms, an increase in the nonreducible forms, deamidation and Met oxidation was predominantly observed under light stress. The monoclonal antibody produced in glass bioreactors that were protected from light behaved similar to the one produced in the larger scale. Our data clearly indicate that care should be taken when glass bioreactors are used in cell culture studies during monoclonal antibody production.

Analysis of Tubespins as a suitable scale‐down model of bioreactors for high cell density CHO cell culture

“…The majority of cell lines evaluated showed higher acidic variants in BR. Deamidation is a common acidic variant that can increase with extracellular incubation during cell culture . Because of shorter residence time in TS, deamidation was less prevalent at this scale, also confirmed by our preliminary characterization of acidic fractions in mAb B anion exchange chromatography (Figure C, characterization results not shown).…”

Effect of manufacturing temperature and storage duration on stability of chemically defined media measured with LC‐MS/MS

“…In our opinion, the impact of CDM preparation parameters on process robustness is a rather neglected and thus far not well‐understood topic in therapeutic protein production. However, when considering the impact of CDM on cell growth, productivity and protein quality, it becomes obvious that monitoring of media components is advantageous . So far, media makeup is defined by strict standard operating procedures with narrow operating ranges.…”

The Effects of Light-Accelerated Degradation on the Aggregation of Marketed Therapeutic Monoclonal Antibodies Evaluated by Size-Exclusion Chromatography With Diode Array Detection

“…21 Recent research also demonstrated that exposing mAbs to light during their production process clearly alters the charge variants profile of the final product. 22 There is therefore extensive evidence that photodegradation leads primarily to chemical changes in single amino acids of proteins and that trp, tyr, phe, and cys are the primary targets of photodegradation. In addition, photodegradation can also promote multiple cross-linking reactions due to dityrosine or disulfide formation and to noncovalent aggregation.…”