Mammalian cells, particularly Chinese hamster ovary cells, are the dominant system for the production of protein-based biotherapeutics, however, product degradation, particularly of Fc-fusion proteins, is sometimes observed that impacts the quality of the protein generated. Here, we identify the site of fragmentation of a model immunoglobulin G1 Fc-fusion protein, show that the observed clipping and aggregation are decreased by reduced temperature culturing, that the fragmentation/clipping is intracellular, and that reduced clipping at a lower temperature (<37°C) relates to mesenger RNA (mRNA) translation elongation. We subsequently show that reduced fragmentation can be achieved at 37°C by addition of chemical reagents that slow translation elongation.
View Article and Find Full Text PDFChinese hamster ovary (CHO) cells are the leading mammalian cell expression platform for biotherapeutic recombinant molecules yet some proteins remain difficult to express (DTE) in this, and other, systems. In recombinant cell lines expressing DTE proteins, cellular processes to restore proteostasis can be triggered when the folding and modification capabilities are exceeded, including the unfolded protein response and ER-associated degradation (ERAD) and proteasomal degradation. We therefore investigated whether the proteasome activity of CHO cells was linked to their ability to produce recombinant proteins.
View Article and Find Full Text PDFThe data presented in this article relates to the manuscript entitled 'Engineering of Chinese hamster ovary cell lipid metabolism results in an expanded ER and enhanced recombinant biotherapeutic protein production', published in the Journal Metabolic Engineering [1]. In the article here, we present data examining the overexpression of the lipid metabolism modifying genes and in CHO cells by densitometry of western blots and by using mass spectrometry to investigate the impact on specific lipid species. We also present immunofluorescence data at the protein level upon SCD1 and SREBF1 overexpression.
View Article and Find Full Text PDFChinese hamster ovary (CHO) cell expression systems have been exquisitely developed for the production of recombinant biotherapeutics (e.g. standard monoclonal antibodies, mAbs) and are able to generate efficacious, multi-domain proteins with human-like post translational modifications at high concentration with appropriate product quality attributes.
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