Impact of S-sulfocysteine on fragments and trisulfide bond linkages in monoclonal antibodies

ABSTRACT

The quality of recombinant proteins such as monoclonal antibodies produced using Chinese hamster ovary cell-based mammalian systems is dependent on many factors, including cell line, process and cell culture media. Due to these factors, the generated product is heterogeneous and may have chemically-induced modifications or post-translational modifications that affect antibody stability, functionality and, in some cases, patient safety. This study demonstrates that S-sulfocysteine, a cysteine derivative, can increase the antibody specific productivity in different cell lines cultivated with different processes while minimizing trisulfide linkages in generated mAbs, mainly between heavy and light chain. The supplementation of a cell culture feed with S-sulfocysteine also proved to be useful to reduce the percentage of antibody fragments generated from the monoclonal antibody. Overall, this new component used in the upstream process allows a reduction of product heterogeneity.

KEYWORDS:

• Critical quality attributes
• Fed-batch
• fragments
• monoclonal antibodies
• productivity
• S-sulfocysteine
• trisulfide

Disclosure of potential conflicts of interest

Ronja Seibel, Alisa Schnellbaecher, Susanne Bohl, Maria Wehsling and Aline Zimmer are employees of Merck, Darmstadt, Germany.

Acknowledgments

The authors would like to thank Jonathan Kaiser for the samples of the mAb4 produced using cell line 4 and Sascha Pering for insightful scientific discussions and critical review of the manuscript.

Funding

This study was entirely funded by Merck, Darmstadt, Germany.