title: Versatile microscale screening platform for improving recombinant protein productivity in Chinese hamster ovary cells.
abstract: Chinese hamster ovary (CHO) cells are widely used as cell factories for the production of biopharmaceuticals. In contrast to the highly optimized production processes for monoclonal antibody (mAb)-based biopharmaceuticals, improving productivity of non-mAb therapeutic glycoproteins is more likely to reduce production costs significantly. The aim of this study was to establish a versatile target gene screening platform for improving productivity for primarily non-mAb glycoproteins with complete interchangeability of model proteins and target genes using transient expression. The platform consists of four techniques compatible with 96-well microplates: lipid-based transient transfection, cell cultivation in microplates, cell counting and antibody-independent product titer determination based on split-GFP complementation. We were able to demonstrate growth profiles and volumetric productivity of CHO cells in 96-half-deepwell microplates comparable with those obtained in shake flasks. In addition, we demonstrate that split-GFP complementation can be used to accurately measure relative titers of therapeutic glycoproteins. Using this platform, we were able to detect target gene-specific increase in titer and specific productivity of two non-mAb glycoproteins. In conclusion, the platform provides a novel miniaturized and parallelisable solution for screening target genes and holds the potential to unravel genes that can enhance the secretory capacity of CHO cells.
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark (DTU), Hørsholm, Denmark.
authors.forename: Henning Gram
authors.initials: HG
authors.lastname: Hansen
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark (DTU), Hørsholm, Denmark.
authors.forename: Claes Nymand
authors.initials: CN
authors.lastname: Nilsson
authors.affiliation: Department of Systems Biology, Technical University of Denmark (DTU), Lyngby, Denmark.
authors.forename: Anne Mathilde
authors.initials: AM
authors.lastname: Lund
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark (DTU), Hørsholm, Denmark.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kol
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark (DTU), Hørsholm, Denmark.
authors.forename: Lise Marie
authors.initials: LM
authors.lastname: Grav
authors.affiliation: Department of Proteomics and Nanobiotechnology, Royal Institute of Technology (KTH), Stockholm, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Lundqvist
authors.affiliation: Department of Proteomics and Nanobiotechnology, Royal Institute of Technology (KTH), Stockholm, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Rockberg
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark (DTU), Hørsholm, Denmark.|Department of Biological Sciences, KAIST, Daejeon, Republic of Korea.
authors.forename: Gyun Min
authors.initials: GM
authors.lastname: Lee
authors.affiliation: Department of Systems Biology, Technical University of Denmark (DTU), Lyngby, Denmark.
authors.forename: Mikael Rørdam
authors.initials: MR
authors.lastname: Andersen
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark (DTU), Hørsholm, Denmark.
authors.forename: Helene Faustrup
authors.initials: HF
authors.lastname: Kildegaard
mesh_terms: D000818:Animals; D016466:CHO Cells; D018929:Cell Culture Techniques; D006224:Cricetinae; D003412:Cricetulus; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D017930:Genes, Reporter; D006031:Glycosylation; D057166:High-Throughput Screening Assays; D054730:Protein Interaction Domains and Motifs; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D015203:Reproducibility of Results
chemical_list: D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins