(570c) The Potential of Small Molecules to Modulate Glycosylation By Media Design

The Potential of Small Molecules to Modulate Glycosylation by Media Design

David Brühlmann, Anaïs Muhr, Jürgen Hemberger, Markus Sauer, Henri Kornmann, Martin Jordan and Hervé Broly

Background and novelty
A large number of recent publications demonstrate the effect of cell culture media on post-translational modifications of recombinant proteins¹. This study aims to extend the toolbox of media design beyond the commonly known media components. We identified and tested a large variety of cell culture compatible chemical components such as pigments and sugar derivatives in industrial relevant Chinese hamster ovary cell lines (CHO) expressing recombinant antibodies.

Experimental approach
The cells were cultivated in fed-batch mode cultures using shaking 96-deepwell plates, and process performance such as viable cell density, viability and product titer were monitored. Supernatants of each culture were purified and N-glycan analysis was performed by CGE-LIF. The findings were confirmed in 30 mL fed-batch shake tube cultures and 15 mL micro-scale bioreactors (ambr15^TM system) operated at controlled pH and pCO₂.

Results and discussion
The addition of the components at the beginning of the culture exhibited significant changes of the glycosylation profile of the expressed protein. Furthermore, the adjustment of the levels and the supplement addition in the feed instead of the media allowed to fine-tune the effect of the components on glycosylation profile. Finally, the use of some of the tested supplements increased peak cell density to levels above 20 mio viable cells/mL and product titer up to 1.5-fold, while maintaining high viability throughout the culture. These results show that media design alone is sufficient to specifically modulate some of the essential protein quality attributes and to increase productivity, which circumvents the need of modifying the gene expression of the cell line.

¹ D. Brühlmann et al., Tailoring Recombinant Protein Quality by Rational Media Design, Biotechnology Progress [published online ahead of print April 10, 2015], doi: 10.1002/btpr.2089